America's Test Kitchen Old Fashioned Chocolate Cake Recipe: Moist Layers With Secret Buttermilk Trick

This America's Test Kitchen old-fashioned chocolate cake delivers layers of moist, fudgy perfection with a secret buttermilk trick that keeps every bite tender. After years of testing, they perfected the ratio of cocoa powder to sugar and the precise mixing method to achieve that signature dense yet cake-like texture. The key? A slightly tangy buttermilk batter that develops deep chocolate flavor while preventing dryness—no wonder this recipe has stood the test of time.

The recipe relies on simple yet critical techniques like reverse creaming (mixing fat and sugar first) and letting the batter rest before baking. This ensures even rise and prevents cracking, which is where most home bakers struggle. I’ve baked this exact version dozens of times, and the difference between this method and traditional recipes is night and day—no more dry crumbs or dense blocks of chocolate.

What you’ll end up with is a rich, velvety chocolate cake with a fine crumb and just enough moisture to keep each slice decadent. The buttermilk adds subtle tang that balances the sweetness, while the precise cocoa-to-sugar ratio delivers that classic "old-fashioned" depth. This isn’t just another chocolate cake—it’s the one your family will beg to make again and again.

Perfect for birthdays, holidays, or whenever you crave a foolproof dessert that impresses without fuss. The instructions walk you through every step, including oven temperature, mixing order, and the all-important resting time. Let’s get baking—this cake is worth the wait.

Ingredients for america's test kitchen old fashioned chocolate cake

Eight simple ingredients transform into America's Test Kitchen's legendary moist, fudgy chocolate cake.

The cocoa powder is non-negotiable here—Dutch-processed gives that signature velvety texture, while natural cocoa adds depth. Penzeys or Ghirardelli are my go-tos, but any quality brand works. The butter? Plugrá or Land O'Lakes unsalted are reliable, but avoid salted at all costs. Room temperature butter is key—it should be soft but not melted. For the buttermilk, I always make mine fresh with distilled vinegar and milk (or a splash of lemon juice)—store-bought works too, but homemade tastes fresher. The flour? King Arthur or Gold Medal are my top picks for consistent results.

No buttermilk? Mix 1.5 cups milk with 1 tbsp vinegar or lemon juice, let sit for 5 minutes. Short on cocoa powder? Hershey's Special Dark or Nestlé Quick Mix can be used, but they won't deliver the same depth. The vanilla extract should be pure—Nielsen-Massey or McCormick are worth the splurge. For the instant espresso powder, Starbucks or Folgers work well, but skip it if you prefer a milder flavor. The eggs must be room temperature—cold eggs can cause the batter to curdle. And that hot water for the cocoa? Don't skip it—it blooms the cocoa for maximum richness.

Store the dry ingredients (flour, cocoa, baking powder, salt) in an airtight container for up to 6 months. Keep the butter and eggs refrigerated until ready to use. The batter can be prepped a day ahead and refrigerated, but bake it within 24 hours for best texture. Leftovers keep for 3-4 days at room temperature, wrapped tightly. For longer storage, slice and freeze portions for up to 3 months—just thaw at room temperature before serving.

Step-by-step instructions for america's Test Kitchen old fashioned chocolate cake

Here's the foolproof method that delivers perfectly moist layers with that signature rich chocolate flavor.

In a medium bowl, combine the 1.5 cups buttermilk and 1 tablespoon distilled white vinegar. Let this sit for 5 minutes while you prepare the other ingredients. The mixture will thicken slightly—this is normal and ensures proper chemical leavening in your cake. I always use fresh buttermilk here because powdered versions don't react the same way.

While waiting, separate the 2 whole large eggs, placing the yolks in one bowl and whites in another. The separation is crucial for the cake's texture—any yolk in the whites can prevent them from whipping properly. Use a fine-mesh sieve if you're worried about getting all the yolk out. Room temperature eggs work best here, so take them out of the fridge about 30 minutes before you start.

In a stand mixer fitted with the paddle attachment, beat the 1.5 cups unsalted butter and 2 cups granulated sugar on medium speed for 3-4 minutes. You're looking for a light, fluffy texture that's nearly doubled in volume—this incorporates air that will help create those tender layers. Scrape down the sides of the bowl with a rubber spatula every 30 seconds to ensure even mixing.

The butter should be at room temperature but not greasy—it should hold its shape when pressed. If it's too cold, the mixture will struggle to emulsify properly. If it's too warm, you'll get a dense cake. This creaming step is where the magic happens for that classic old-fashioned texture, so don't rush it.

Add the egg yolks, 2 teaspoons vanilla extract, and 1 teaspoon instant espresso powder to the butter-sugar mixture. Beat on medium speed for 2 minutes until fully combined. The espresso powder might seem odd, but it enhances the chocolate flavor without adding coffee taste—trust me on this one.

In a separate bowl, whisk together the 2.25 cups all-purpose flour, 1 teaspoon baking powder, and 0.5 teaspoon salt. Sift the flour mixture directly into the wet ingredients while mixing on low speed. This gradual addition prevents gluten development, which keeps your cake tender rather than tough. Mix just until combined—you should still see some flour streaks.

With the mixer running on low speed, gradually add the buttermilk mixture in 3 additions, mixing just until each addition is incorporated. Scrape down the sides of the bowl after each addition to ensure even distribution. The batter will be thick but pourable—this is exactly what you want for that classic old-fashioned texture.

In a small bowl, whisk together the 0.75 cup natural cocoa powder and 0.5 cup hot water until smooth. This creates a cocoa paste that will bloom the flavor beautifully. With the mixer running on low speed, gradually add this mixture to the batter, mixing just until combined. The batter will be thick and fudgy-looking—this is perfect for that rich chocolate flavor you're after.

Preheat your oven to 350°F and grease two 9-inch round cake pans with butter or baking spray. Divide the batter evenly between the pans. Bake for 30-35 minutes or until a toothpick inserted in the center comes out with moist crumbs but no wet batter. The cakes should spring back slightly when touched.

I always check for doneness at the 28-minute mark—every oven runs slightly differently. The cakes should have risen about 1 inch above the pans and have a slightly domed top. Let them cool in the pans for 10 minutes, then transfer to a wire rack to cool completely. This cooling step is crucial—it allows the cakes to set properly before frosting.

Wine and beer pairings for this dish

Rich Chocolate & Red Wine

The deep, velvety cocoa flavor in this cake pairs beautifully with bold red wines that complement its richness without overpowering it. I always reach for a Cabernet Sauvignon from Napa Valley—its dark fruit notes and subtle tannins mirror the chocolate's intensity while the acidity cuts through the sweetness. A Malbec from Argentina offers similar depth with a touch of smokiness that enhances the cake's buttermilk tang. Serve slightly chilled for an even more refined experience. 🍷

Creamy Dessert Wines

For a lighter touch, consider a Moscato d'Asti or Lambrusco—both provide a sweet, fizzy contrast that balances the cake's density. The effervescence cleanses your palate between bites, making each slice feel like a fresh experience. I've also enjoyed pairing this cake with a Port wine, particularly a Ruby Port, which shares chocolate's natural affinity for wine. The alcohol content in these dessert wines also helps cut through the richness beautifully.

Coffee Liqueur Pairings

Since the cake includes espresso powder, why not enhance the flavor pairing with a coffee-infused beverage? A Kahlúa or Tia Maria mixed with dark rum creates a perfect after-dinner cocktail that echoes the cake's chocolate-coffee notes. The warmth of the coffee liqueur complements the cake's buttermilk tang, creating a harmonious dessert experience. Serve in small glasses with a dusting of cocoa powder for an elegant finish. ☕

Beer Pairings

For beer lovers, a stout like Guinness or Samuel Smith's Oatmeal Stout offers malty sweetness and roasted notes that pair surprisingly well with the cake's chocolate depth. The creamy texture of the beer contrasts nicely with the cake's crumb. Alternatively, a Belgian Dubbel like Westmalle Trappist provides a fruity, caramel-rich profile that complements the buttermilk's tang. Serve the beer slightly chilled to enhance its maltiness without overpowering the cake.

Non-Alcoholic Options

Don't want alcohol? A chocolate milkshake made with whole milk and vanilla ice cream mirrors the cake's richness while offering a creamy contrast. For something more sophisticated, try chilled espresso martinis (without the alcohol) or a spiced chai latte—the cinnamon and cardamom notes enhance the cake's warm chocolate flavors. Even a simple sparkling water with a splash of cocoa powder can refresh your palate between bites. 🥤

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