Coffee and chocolate have long been a popular pairing: The bitterness of the coffee enhances the chocolate’s fruity, bittersweet notes, adding a pleasant depth of flavor. This affinity is why you’ll often see a teaspoon or so of instant espresso or coffee in brownies and chocolate mousse. My favorite way to enjoy the combination, though, is the most obvious: as a mocha. The espresso has just enough bitterness to balance the rich sweetness of chocolate and milk, making it a luxurious beverage. That flavor profile is especially delicious in desserts. But why stop at a teaspoon of espresso powder in a dessert when you could just make the whole thing mocha flavored?

That brings me to the tres leches cake, which typically consists of a vanilla cake generously soaked in whole milk or heavy cream, along with sweetened condensed milk and evaporated milks, then topped with whipped cream. The cake soaks up the dairy, becoming incredibly moist and almost custard-like. The vanilla cake in classic tres leches has a neutral flavor that makes it a great base for other flavors, and I decided to riff on it by incorporating the flavors of a mocha. The bitterness of the coffee and chocolate complements the rich milky flavors of tres leches cake, and helps temper the dessert’s intense sweetness.

Instead of going the traditional vanilla route, I  make my sponge cake with a combination of cocoa powder and instant espresso, then soak it in a mixture of heavy cream, evaporated milk, and sweetened condensed milk—all  flavored with instant espresso. The final touch is a blanket of whipped cream and a light dusting of cocoa powder and cinnamon. 

3 Tips for Making a Stellar Tres Leches Cake

Make a light, fluffy cake. I like to use a chiffon cake as a base for my tres leches cake, as it has an airy crumb that’s perfect for soaking up liquids. Its light texture comes from whipped egg whites that are gently folded into the batter. So, to make a sturdy meringue, it’s crucial to whip the egg whites at a low speed for a long time instead of quickly whipping them at high speed. As Serious Eats senior editor Genevieve touches on in her chocolate mousse recipe, the air bubbles in egg whites become smaller and more stable the longer they’re whisked, resulting in a meringue that’s less likely to deflate—and a delightfully light cake. 

Reach for Dutch-process cocoa powder. As former editor Stella Parks notes in her guide to the best cocoa powders, the ingredient is typically categorized as either natural or Dutch-process. According to Stella, most natural cocoa powders come from poor quality cocoa beans “that have had almost all of their cocoa butter removed,” resulting in a bland powder lacking rich chocolate flavor. 

On the other hand, most Dutch-process cocoa powders come from better beans and have twice the amount of fat as natural cocoa powder. This results in “a slightly alkaline cocoa powder that’s higher in fat, lower in starch, and more aromatic all around, with a mahogany color and a flavor profile that emphasizes cocoa’s darker, nuttier, earthier tones.” So for a cake with maximum chocolate flavor—especially one like this in which all of the chocolate flavor comes from cocoa powder‚ it’s crucial to reach for a good-quality Dutch-process cocoa powder.

Use instant espresso powder. There are many ways to incorporate coffee into a dessert, including brewed coffee or espresso, coffee extract, or instant espresso powder. Here, I reach for instant espresso powder, which is made by freeze-drying concentrated espresso. Its concentrated flavor makes it ideal for incorporating into desserts, as it brings bold coffee flavor without introducing a bunch of liquid to the cake batter.

This tres leches cake comes together fairly quickly, but then it needs to soak for at least three hours or up to a day. This lengthy soak means the cake is easy to make ahead; that and the fact that the cake serves 15 people makes it perfect for parties.

For the Cake: Adjust oven rack to middle position and preheat to 325°F (160°C). Lightly grease a 9- by 13-inch baking pan with vegetable oil.

Using a fine-mesh sieve, sift flour, baking powder, and cocoa powder into a medium bowl; set aside. In a small bowl, combine milk and instant espresso powder. Whisk until espresso powder is dissolved, then stir in vegetable oil. Set aside.

In the bowl of a stand mixer fitted with the whisk attachment, combine egg whites and salt. Whip on medium speed until egg whites begin to froth, about 1 minute. Then, with mixer continuing to run at medium speed, slowly and steadily pour in sugar. Continue to whisk until meringue is glossy and reaches stiff peaks, about 8 minutes. Add yolks and beat until just combined

With the stand mixer running on low, sprinkle in about 1/3 of the flour mixture, then drizzle in 1/3 of the milk and coffee mixture. Repeat with remaining flour and milk, and mix, using a flexible spatula to scrape the bowl and beaters as needed, until batter is well combined, 3 to 5 minutes. Using a flexible spatula, scrape the batter into the prepared pan and bake until a toothpick or cake tester inserted comes out clean and cake springs back when gently touched, 30 to 35 minutes. Set the pan on a wire rack and cool completely, about 1 hour. (Clean mixer bowl and set aside.)

For the Soaking Liquid: In a medium bowl, combine heavy cream, evaporated milk, sweetened condensed milk, instant espresso powder, and salt, and whisk until espresso powder has dissolved, about 1 minute.

Run an offset spatula or butter knife around edges of cake to loosen. Invert cake onto a cutting board. Using a serrated knife, carefully remove top of cake to level it; set scraps aside for snacking or another use. Return the cake to the pan and, using a skewer or fork, poke holes across surface of cake. Pour half of the soaking liquid all over the cake. Let liquid fully absorb, about 5 minutes, then pour remaining liquid over cake. Loosely cover baking pan with plastic wrap and refrigerate until fully chilled, at least 2 hours and up to 24 hours.

To Assemble: In the now-clean bowl of a stand mixer fitted with the whisk attachment, combine heavy cream, confectioners’ sugar, 1 1/2 teaspoons cocoa powder, and salt. Beat on medium-high speed until medium-stiff peaks form, 2 to 4 minutes. Using a flexible or offset spatula, spread whipped cream over cake to cover.

Using a fine-mesh sieve, sift remaining 3 tablespoons cocoa powder and cinnamon mixture over whipped cream. Slice and serve.

Special Equipment:

9- by 13-inch baking pan, fine-mesh sieve, stand mixer, flexible spatula, toothpick or cake tester, offset spatula or butter knife

Make-Ahead and Storage:

Once baked and cooled (through step 4), the cake can be tightly wrapped in plastic and refrigerated for up to 1 week or frozen for up to 3 months. 

The cake should be served within 24 hours of soaking.

This summer, I spent five months living and working at Camp Denali, a wilderness lodge in Denali National Park, Alaska. Backcountry hiking is the main attraction, and on each outing, our naturalist guides carry more than 10 pounds of gear, including a slew of emergency preparedness supplies. But the item that I find most important isn’t truly an “essential.” It’s a thermos full of hot chocolate. 

Our guides carry Stanley thermoses on every outing into the park so guests can enjoy a hot beverage after a long day of hiking. Ranked as one of the best thermoses in our review, the Stanley Classic Legendary bottle keeps beverages steaming hot for many hours—but most impressively, the thermos is basically indestructible. In fact, Camp Denali has used the same thermoses (cleaned after every use, of course) for over 30 years. 

What's a Thermos Good For?

If you like to bring hot drinks on the go, a thermos is an excellent option. It keeps the contents hot (and out of the “temperature danger zone” where bacteria can grow) for up to 24 hours, eliminating the need for refrigeration or reheating.

What’s the difference between a travel mug and a thermos, and how do you know which one best suits your needs? “Compared to travel mugs, thermoses are bigger (usually at least one liter compared to 16 ounces), have thicker vacuum insulation, and have screw-on, leak-proof caps without a sipping port,” explains former Serious Eats writer Jesse Raub in his review of thermoses. “They’re better at retaining heat for longer periods than travel mugs, and most are secure enough to toss into any bag without fear of coffee (or iced tea) leaking.” 

Pack a thermos full of hot chocolate for a family trip to the ice rink, or tote a carafe of coffee to the office. No fear of spillage, and no need for reheating. (PS: If you want a thermos to keep your lunch warm, check out the best food thermoses.)

What Makes the Stanley Thermos Great?

There are two primary ways to judge a thermos’ effectiveness. First, its insulating properties: Does it keep the contents at the desired temperature (warm or cold), and for how long? Most of the thermoses in our review—including the Stanley Classic Legendary bottle—passed this trial easily, maintaining a temperature of at least 170°F (hot enough to burn most people’s tongues) for eight hours. 

The Stanley bottle performed exceptionally well in the hot and cold retention trials, but so did plenty of other thermoses, including ones from Zojirushi and MiiR. The most distinctive factor, then, in determining the quality of a thermos is its durability. This is the area where Stanley distinguishes itself: It has survived more than 30 years of heavy use in the Alaskan backcountry.

Manufactured in 1987, Camp Denali’s Stanley thermoses have weathered all kinds of heavy use—jostling around a backpacking pack, rolling around the back of a bus, tumbling down a gravel hill, etc. They’ve certainly endured exterior wear and tear—most of the original green paint has chipped off, revealing the stainless steel body—but they still work just as well as new. 

That’s because Stanley thermoses are built to last. They’re constructed from 18/8 stainless steel, with double-wall vacuum insulation that keeps heat in and prevents spills. As long as the vacuum still seals properly, an older thermos will continue to perform. The vintage thermoses reliably keep water steaming hot for more than six hours, so after a long day’s trek, I’m always rewarded with a hot cup of tea or cocoa.

In addition to its impressive durability, there are a few design details I appreciate about the Classic Legendary thermos. The thermos itself is tall and thin—easy to slip into the water bottle sleeve on a backpack—and it comes with a collapsible handle, making it comfortable to carry. (If you prefer one without a handle, that’s an option, too.) The bottle’s lid doubles as a drinking cup, so it’s easy to pour yourself a hot beverage on the go. Beneath the lid, a twist-and-pour stopper minimizes the risk of spillage and further limits the liquid’s exposure to the elements, keeping it hotter for longer. Plus, they last a lifetime—just ask the guides in Alaska.

FAQs

How much liquid does the Stanley thermos hold?

The Stanley thermos comes in four sizes: 1.1 quarts, 1.5 quarts, two quarts, and 2.5 quarts. We use the 2.5-quart model, which holds 10 cups of liquid, to serve hot beverages to 10 to 12 people.

How long will the Stanley thermos stay hot?

According to Stanley, the thermos will stay hot for 24 hours. In Serious Eats’ tests, the Stanley thermos maintained a temperature of at least 170°F for eight hours and 135°F for 24 hours.

How do I know if my thermos’s vacuum seal is broken?

If your thermos is leaking, that’s a sure sign that the vacuum seal is no longer effective. If you open your thermos after a couple of hours and the contents are no longer hot, that’s another indicator that the vacuum seal has been compromised. If you’re using the thermos exclusively for hot beverages like coffee, the primary risk of a faulty vacuum seal is leakage—annoying, but not necessarily dangerous. If you’re using the thermos for food storage, however, a compromised vacuum seal can result in potentially hazardous bacteria growth.

Why We’re the Experts

• Zoe Denenberg is a chef, baker, and food writer. 
• She has spent the past five-plus years working in kitchens across the country, including an artisanal ice cream shop in Birmingham, Alabama, and a Michelin-starred restaurant in New York City. 
• She is currently the executive chef at Camp Denali, a wilderness lodge in Denali National Park, Alaska, where the Stanley thermos has been a reliable hiking companion for decades.
  

There’s no way around it: If you want to cook, you need a good knife (or two, or three!). My team at Serious Eats has been testing and reviewing them for years, and we’ve noticed a common theme: Great knives don’t often go on sale. Although a well-made blade is worth the investment, I’ll never turn down a nice knife deal. This year, I went on the hunt, searching through pages and pages of Amazon’s Big Spring Sale in search of great discounts on kitchen knives. I found 10 outstanding deals on Serious Eats-approved knives, including chef’s knives, paring knives, and accessories, like honing rods and sharpeners, up to 48% off at Amazon’s sale.

One of Our Favorite Western-Style Chef’s Knives: Mercer Culinary 8-Inch Genesis

Mercer is a tried-and-true brand of tools and knives in culinary schools. The Genesis has long reigned supreme as a winner in our chef’s knives review. I have no complaints about the blade—it’s sharp and durable—but it’s the handle that really delivers. Made from a combination of rubber and plastic, it’s comfortable to hold, giving the cook a confident grip. Right now, it’s discounted by almost 40%.

A Workhorse Petty Knife: Victorinox 6-Inch Fibrox Pro Chef’s Knife

Petty knives are sized between 5.5 and six inches, making them just as useful as chef’s knives but a bit more nimble. They’re a must-have upgrade for cooks who want a knife with outstanding versatility. This one from Victorinox is a winner in our petty knives review. It’s really sharp, and the blade is slightly curved. This makes it useful for chopping in addition to more traditional petty knife tasks, like slicing tomatoes and maneuvering around chicken joints.

A Beautiful, Sharp Paring Knife: Shun Classic 3.5-Inch Paring Knife

Shun knives are favored by pro cooks—they’re meticulously crafted, hold an incredible edge, and look beautiful. They’re also rarely on sale, which is why I enthusiastically encourage you to take advantage of this 20% discount. Normally $125, this 3.5-inch paring knife is the right size for intricate, precise tasks, like segmenting citrus.

A New Haven-Style Oyster Knife: Dexter Russell 2.75 Inch New Haven Style Oyster Knife

Oyster knives are single-purpose tools, but they deserve a place in your utensil drawer. When you need one, nothing else will do. This one, which has a slightly curved blade, is ideal for cracking into deep, large oysters—not something all knives can do. My colleague Grace, who lives in Rhode Island and is our team's oyster expert, highly recommends it. It’s a great price right now; buy it once and never be without the right tool for oyster night again.

A Super Sharp Slicing Knife: Victorinox Fibrox Pro 12-Inch Slicing Knife with Granton Blade

The dimpled edges of this long, elegant knife make it ideal for slicing meat. In fact, we named it the best slicing knife in our review. Its non-serrated edge is wicked sharp, and the 11-inch blade makes it a great choice for large meat, like brisket. It’s a good buy any time of year, but during the Amazon Big Spring Sale, it’s just about 30% off. 

A Steal of a Deal Carving Knife: Mercer Culinary 10-Inch Carving Knife

A proper carving knife should have a tapered tip for finagling around bones. This one from Mercer is the right size and shape and is especially nimble. It’s made from the same steel as another Serious Eats-favorite carving knife from Wüsthof, but retails for a lot less.

A Solid, Sturdy Set of Steak Knives: Zwilling Steak Knife Set

Amidst ones that cost hundreds, this set of four blades wowed us during our review of steak knives. They easily sliced through skirt steak and filet mignon. Although the blades are lightly serrated and will dull with time, it’s hard to beat the price, especially when it’s $15 off.

Rock-Solid Kitchen Shears: Kershaw Taskmaster Kitchen Shears

If you want a pair of kitchen shears that can snip a handful of chives and effortlessly spatchcock a chicken, this is the one for you. They were named the most durable kitchen shears in our review and have a few fancy extra features (who doesn’t love a nutcracker and screwdriver tip add-on?). Normally over $40, they’re on sale right now for about $25.

A Versatile Honing Steel: Zwilling Kramer Accessories 12.25-Inch Double-Cut Honing Steel

Typically, a honing rod isn’t all that helpful when your knives are dull—they’re best for quick touch-ups. But this one has coarse and smooth sides, so you can get a sharp edge, and then maintain it between chopping sessions. The rod itself is 12 inches long, helpful for spiffing up extra-long blades. The $20 discount is impressive, considering this is a trusted brand and a high-quality tool.

A Pull-Through Knife Sharpener for Beginners: Zwilling J.A. Henckels 4-Stage Pull Through Knife Sharpener

Our team prefers whetstones and electric sharpeners over pull-through sharpeners (you can read more about why here), but I’ll be the first to admit that a pull-through option is often the type I recommend to new cooks. It’s easy to use, doesn’t require any special skills, and costs lots less than electric sharpeners. In fact, this sharpener from Zwilling is the only roll-through model Serious Eats recommends. It offers both coarse and fine sharpening options and can accommodate Japanese knives and Western-style knives.

FAQs

When is the Amazon Big Spring Sale in 2025?

It runs from March 28 through March 31 this year. If you want to shop more kitchen sales, you can check out our other favorite deals here or Amazon’s spring sale hub.

Why We’re the Experts

• Rochelle Bilow is an editor at Serious Eats.
• Rochelle is a culinary school graduate and former line cook. Previously, she worked at Bon Appétit and Cooking Light magazines. 
• At Serious Eats, we have tested hundreds of knives. We regularly revisit our reviews to make sure our recommendations and findings are current.