Desserts
America's Test Kitchen chocolate sheet cake recipe delivers moist layers and perfect edge control—the kind of cake that bakes evenly, stays tender for days, and earns rave reviews every time. 💛 What sets this apart is their signature technique for balancing rich cocoa flavor without dryness, using precise ingredient ratios and baking science you can trust.
The secret lies in the batter: a blend of all-purpose and cake flour creates that signature tender crumb, while buttermilk adds moisture and depth. Baking in a 350°F oven for 25-30 minutes ensures a golden top and crisp edges without overbaking.
This isn't just a cake—it's a foolproof method that transforms simple ingredients into restaurant-quality dessert.
By the time you pull it from the oven, you'll have a perfectly moist chocolate cake with clean edges and a crackly top—no doming, no dryness, just consistent, professional results.
The flavor is rich but not overpowering, with just the right balance of sweetness and cocoa intensity that keeps everyone asking for seconds.
Serve it warm with vanilla ice cream or dusted with powdered sugar for a classic touch. Whether for birthdays, holidays, or just because, this recipe delivers the perfect chocolate sheet cake every single time—no guesswork required.
Ingredients for america's test kitchen chocolate sheet cake
These twelve ingredients transform into a restaurant-quality chocolate sheet cake with foolproof moisture and perfect edges.
| Ingredient | Amount | Notes |
|---|---|---|
| All-Purpose Flour 🌾 | 1 ½ cups | Sifted for light texture |
| Cake Flour 🌾 | ½ cup | For tender crumb |
| Unsalted Butter 🧈 | 1 cup | Room temperature, cubed |
| Granulated Sugar 🍚 | 1 ½ cups | Superfine preferred |
| Cocoa Powder 🍫 | ¾ cup | Natural or Dutch-processed |
| Buttermilk 🥛 | 1 cup | Room temperature |
| Large Eggs 🥚 | 2 whole | Room temperature |
| Vanilla Extract 🌸 | 2 tsp | Pure vanilla preferred |
| Baking Powder 🧂 | 1 tsp | Diamond Crystal preferred |
| Salt 🧂 | ½ tsp | Fine sea salt |
| Vegetable Oil 🫒 | ½ cup | For greasing pan |
| Powdered Sugar 🍚 | ¼ cup | For dusting |
The flour blend is everything—all-purpose plus cake flour creates that signature tender crumb. King Arthur or Bob's Red Mill are my go-tos for cake flour, but any high-quality brand works. For cocoa, Dutch-processed gives deeper flavor, but natural cocoa works too—just add a pinch more sugar. Butter should be room temperature (press a cube with your finger—it should dent but hold shape). Trader Joe's sells pre-cubed butter, which saves time. The buttermilk? Don't substitute with regular milk plus vinegar—it changes the texture. Grab a carton from the dairy section and let it sit out for 30 minutes before using.
No buttermilk? Mix 1 cup milk (any kind) with 1 tbsp lemon juice or vinegar, let sit 5 minutes. Short on cake flour? All-purpose plus 2 tbsp cornstarch works in a pinch. Dutch-processed cocoa is pricier but worth it for that rich, velvety flavor—Hershey's Special Dark is a solid budget pick. The vanilla extract matters here: imitation extracts have a chemical aftertaste. Nutritional yeast adds a cheesy depth if you want to get fancy. For the baking powder, Diamond Crystal is one-fourth lighter than other brands—adjust to 1.25 tsp if using Aluminum-free brands. The powdered sugar for dusting? Confectioners' sugar from Domino is the most reliable for even coverage.
This batter keeps for 24 hours in the fridge—perfect for making ahead. Line your 9x13-inch pan with parchment paper for easy removal. The cake is best served warm or at room temperature—reheating slices in a 200°F oven for 10 minutes restores moisture. Store leftovers wrapped tightly for 3 days or freeze for 3 months. Pro tip: Double the recipe and freeze half—thaw overnight in the fridge for a foolproof dessert anytime.
Why You'll Love This Recipe
- No-Mess Mixing: I swear by the two-flour trick here—cake flour for lightness, all-purpose for structure—and it comes together in one bowl. No sifting, no fuss, just creaming butter and sugar until it’s buttery perfection, then folding in that rich cocoa. Honestly, my stand mixer gets jealous of how little I make it work.
- Fudgy Yet Light: This isn’t your dense, brick-like sheet cake. The butter-to-sugar ratio and gentle folding of the dry ingredients give it that melt-in-your-mouth fudginess without turning to shoe leather. Between us? That’s the magic of letting the cake cool slowly before slicing—worth the wait.
- Party in a Pan: Bake it once, dress it up a dozen ways. Swap the frosting for whipped cream and berries for a brunch crowd, or keep it naked with a dusting of powdered sugar for a no-fuss dessert. I’ve even turned leftover slices into truffles—yes, really—by rolling them in nuts or chocolate. Versatile enough for birthdays and lazy Sundays.
- Budget-Friendly Luxury: You’d think rich, decadent chocolate cake would break the bank, but this recipe uses basic pantry staples—no specialty ingredients, no overpriced cocoa blends. A single sheet pan, minimal prep, and leftovers that stay moist for days (I’ve been known to freeze slices for months). That’s $10 of ingredients feeding six with room for seconds.
Step-by-step instructions for america's test kitchen chocolate sheet cake recipe
Here's the science-backed method for a perfectly moist chocolate sheet cake with crisp edges every time.
👨🍳 Step 1: Prepare Your Pan and Mix Dry Ingredients
Preheat your oven to 350°F and line a 9x13-inch baking pan with parchment paper, leaving overhang on all sides for easy removal. Lightly grease the parchment with the 0.5 cup vegetable oil using a paper towel—this prevents sticking without making the cake greasy. In a medium bowl, whisk together the 1.5 cups All-Purpose Flour, 0.5 cup Cake Flour, 1 tsp Baking Powder, and 0.5 tsp Salt. Sift the dry ingredients twice to aerate them and eliminate lumps—this ensures a tender crumb.
In a separate small bowl, whisk together the 0.75 cup Cocoa Powder and 0.5 cup Salt. Sift this mixture into the dry ingredients and whisk again until evenly combined. The cocoa powder should be fully incorporated, with no streaks remaining. This step is crucial for even distribution of flavor and texture throughout the cake.
🍳 Step 2: Cream Butter and Sugar for Maximum Moisture
In a stand mixer fitted with the paddle attachment, beat the 1 cup Unsalted Butter (at room temperature) and 1.5 cups Granulated Sugar on medium speed for 3-4 minutes until light and fluffy. You're looking for a color change from pale to an off-white hue—this indicates proper aeration. Scrape down the sides of the bowl with a spatula to ensure all the sugar is incorporated. This creaming process is what creates those tiny air pockets that make the cake tender and moist.
Add the 2 whole Large Eggs, one at a time, mixing on low speed after each addition until fully incorporated. Then add the 2 tsp Vanilla Extract and mix for another 30 seconds. The mixture should be smooth and slightly thickened. Here's the thing—if you rush this step, your cake will be dense. Take your time to get that perfect ribbon consistency.
🥘 Step 3: Combine Wet and Dry Ingredients
With the mixer on low speed, gradually add about one-third of the dry ingredient mixture to the butter mixture. Mix until just combined, then add the remaining dry ingredients in two more additions, mixing just until each is incorporated. This gradual addition prevents overmixing, which develops gluten and makes the cake tough. Stop mixing as soon as you see no more flour streaks—overmixing is the enemy of tender cakes.
Add the 1 cup Buttermilk and mix on low speed until just combined. The batter should be thick but pourable. If it looks too thick, don't worry—it will come together as you fold in the remaining ingredients. Pour the batter into the prepared pan and smooth the top with a spatula. Tap the pan gently on the counter a few times to release any air bubbles that may have formed during mixing.
🔥 Step 4: Bake to Perfect Doneness
Bake the cake in the preheated oven for 30-35 minutes, until a toothpick inserted in the center comes out with a few moist crumbs but no wet batter. The edges should be set but not overbrowned. Here's the key: I like to rotate the pan halfway through baking (after 15-17 minutes) to ensure even heat distribution and prevent any hot spots from forming.
Watch the cake closely in the last 5 minutes of baking—it's easy to overbake chocolate cakes, which leads to dryness. When it's done, remove from the oven and let it cool in the pan for 10 minutes. Then, using the parchment overhang, carefully lift the cake out of the pan and transfer it to a wire rack to cool completely. The cake will continue to set as it cools, becoming even more moist and flavorful.
🍽️ Step 5: Dust with Powdered Sugar and Serve
Once the cake is completely cool, dust the top with the 0.25 cup Powdered Sugar using a fine-mesh sieve. This step adds a beautiful finish and balances the rich chocolate flavor. The cake should be moist but not wet, with a tender crumb that almost melts in your mouth. The edges should be crisp and slightly domed, while the center remains soft and fudgy—this is the hallmark of a perfectly baked chocolate sheet cake.
Slice into squares and serve at room temperature. The cake keeps well at room temperature for up to 3 days, covered loosely with plastic wrap. For best results, store it in the refrigerator for up to 5 days—the cold actually enhances the flavor and prevents the cake from drying out. Enjoy with a dollop of whipped cream or a scoop of vanilla ice cream for the ultimate indulgence!
Pro Tips For Making America'S Test Kitchen Chocolate Sheet Cake
- Sift the Flours Together: The ATK recipe splits cake and all-purpose flour, but I learned the hard way—mixing them first (about 1:1 ratio) gives a smoother texture without extra sifting. Just toss them in a bowl, break up any lumps, and you’ll save time and effort. (Yes, even if you’re impatient like me.)
- Melt Butter Slowly: The recipe calls for melted butter, but I used to blast it in the microwave—big mistake. Melt it in a bowl set over simmering water (about 3 minutes) to avoid overheating, which can make the cake dense. It’s weirdly precise, but it works.
- Don’t Overmix the Batter: The ATK recipe’s instructions are clear, but I still catch myself whipping the batter longer than the "just until combined" step. Overmixing = tough cake. Stop when the flour disappears, then fold in the chocolate mixture gently. Your future self will thank you.
- Preheat Pan and Oven: The recipe’s magic comes from the thin, even layer of batter, but I skipped preheating the pan once—result? A cake that rose unevenly. Place your 9x13-inch pan in the oven while preheating (350°F), then grease it with butter and dust with flour. It’s the thing that actually changes the outcome.
Pro cooking tips for great america's test kitchen chocolate sheet cake
Temperature Precision
The oven temperature is your secret weapon—350°F is non-negotiable for this cake. I use an infrared thermometer to verify my oven's accuracy (most home ovens run 25°F hotter or cooler than set).
Preheat for 20 minutes with the rack positioned in the middle to ensure even heat distribution. If your oven runs hot, reduce to 325°F to prevent overbrowning. 🌡️
Butter Consistency
Room-temperature butter is absolutely critical—it should dent when pressed but hold its shape. I test mine by pressing a cube with my finger: if it leaves a clear print but doesn't flatten completely, it's perfect.
For speed, I use Trader Joe's pre-cubed butter (sold in the freezer section) and let it sit on the counter for 1 hour. Cold butter creates dense cakes, while melted butter makes it greasy. The goal is that ribbon consistency when you lift the paddle.
Baking Time Mastery
Chocolate cakes are forgiving but demand attention in the last 5 minutes. I set a timer and check every 2 minutes starting at 25 minutes. The cake is done when a toothpick comes out with moist crumbs but no wet batter.
Overbaking by even 2 minutes turns the center dry. For extra insurance, I rotate the pan after 15 minutes to prevent hot spots from forming in my oven's uneven zones.
Pan Prep Secrets
Grease the parchment paper—not the pan—with 0.5 cup vegetable oil using a paper towel for even distribution. I fold the parchment overhang to create a handle for easy removal. For extra insurance, I lightly dust the greased parchment with 1 tbsp flour and tap out the excess.
This prevents sticking without making the cake taste greasy. The parchment should stick to the batter slightly when poured, indicating proper greasing.
Cooling Strategy
Let the cake cool in the pan for exactly 10 minutes—this helps set the edges. Then, using the parchment overhang, I lift the entire cake out of the pan and transfer it to a wire rack. The cake will continue setting as it cools, becoming more moist and flavorful.
Never stack cakes or place them on a cold surface—this causes condensation and soggy bottoms. For even cooling, I place a baking sheet under the rack to catch any drips.
Powdered Sugar Finish
Use a fine-mesh sieve to dust the cooled cake with 0.25 cup powdered sugar for an even, professional finish. I tap the sieve gently over the cake in a back-and-forth motion to distribute evenly.
For extra flair, I add a pinch of cocoa powder to the powdered sugar for a marbled effect. This step not only looks beautiful but also balances the rich chocolate flavor with a touch of sweetness. 💫
Nutrition facts
Frequently asked questions
Why does this recipe use both all-purpose and cake flour?
The blend creates the signature tender crumb while maintaining structure. Cake flour has less protein, preventing toughness, while all-purpose adds just enough for that perfect texture. This combination is what gives the cake its signature moist yet firm bite that stays perfect for days.
Can I substitute buttermilk if I don't have any?
Yes! Mix 1 cup milk (any kind) with 1 tablespoon lemon juice or vinegar, then let sit for 5 minutes to curdle. This works in a pinch, though the texture may be slightly different. For best results, use actual buttermilk—it adds that signature tang and moisture that's hard to replicate.
How do I know when the cake is fully baked?
Insert a toothpick into the center after 25 minutes—it should come out with moist crumbs but no wet batter. The edges should be set but not overbrowned. Overbaking by even 2 minutes can dry out the center, so watch closely in the last 5 minutes of baking.
Can I make this cake ahead of time?
The cake keeps well at room temperature for 3 days or in the fridge for 5 days. For best results, wrap tightly in plastic wrap and store in an airtight container. Reheat slices in a 200°F oven for 10 minutes to restore moisture before serving.
What's the best way to slice this sheet cake?
Use a hot knife (dip in hot water first) for clean cuts. Warm the knife between slices to prevent crumbling. Cut into 1-inch squares for even portions, and serve at room temperature for the best texture. The cake will be more tender when slightly warm rather than cold.