Yellow Sheet Cake with Chocolate Frosting
SERVES 12 TO 15
WHY THIS RECIPE WORKS: For a tender cake with a fine, plush texture, we started by using bleached cake flour. Its altered starch is more absorbent than the starch in unbleached flour, so it can accommodate more liquid, sugar, and fat (we use butter for flavor and vegetable oil for moistness) without collapsing under the extra weight. We combined the ingredients using the reverse-creaming method: First we mixed the dry ingredients—flour, sugar, leavener, and salt—with the fat, and then we beat in the eggs and liquid ingredients. Only a small amount of air was incorporated during mixing, resulting in a superfine texture. For a frosting that would hold its shape even in warm weather, we whipped up a modified American buttercream. Adding hot water reduced the grittiness of the confectioners’ sugar, and a combination of cocoa powder and bittersweet chocolate yielded a frosting with a rich, multidimensional chocolate flavor.
CAKE
4 large eggs plus 2 large yolks
½ cup buttermilk
1 tablespoon vanilla extract
2¼ cups (9 ounces) bleached cake flour
1¾ cups (12¼ ounces) granulated sugar
1¼ teaspoons baking powder
¼ teaspoon baking soda
½ teaspoon table salt
8 tablespoons unsalted butter, softened
½ cup vegetable oil
FROSTING
2¼ cups (9 ounces) confectioners’ sugar
½ cup (1½ ounces) unsweetened cocoa powder
8 tablespoons unsalted butter, softened
¼ cup hot water
¼ teaspoon table salt
2 ounces bittersweet chocolate, melted
- FOR THE CAKE: Adjust oven rack to middle position and heat oven to 350 degrees. Grease and flour 13 by 9-inch baking pan. Combine eggs and yolks, buttermilk, and vanilla in 2-cup liquid measuring cup and whisk with fork until smooth.
- Combine flour, sugar, baking powder, baking soda, and salt in bowl of stand mixer fitted with paddle. Mix on low speed until combined, about 20 seconds. Add butter and oil and mix on low speed until combined, about 30 seconds. Increase speed to medium and beat until lightened, about 1 minute. Reduce speed to low and, with mixer running, slowly add egg mixture. When mixture is fully incorporated, stop mixer and scrape down bowl and paddle thoroughly. Beat on medium-high speed until batter is pale, smooth, and thick, about 3 minutes. Transfer batter to prepared pan and smooth top. Tap pan firmly on counter 5 times to release any large air bubbles.
- Bake until toothpick inserted in center comes out with few crumbs attached, 28 to 32 minutes. Let cake cool completely in pan on wire rack, about 2 hours.
- FOR THE FROSTING: Combine sugar, cocoa, butter, hot water, and salt in bowl of stand mixer fitted with whisk attachment. Mix on low speed until combined, about 20 seconds. Increase speed to medium and continue to mix until smooth, about 1 minute longer, scraping down bowl as necessary. Add melted chocolate and whip on low speed until incorporated. Let sit at room temperature until thickened to spreadable consistency, 30 to 40 minutes.
- Frost cake. Refrigerate until frosting is set, about 20 minutes, before serving.
Photo credit: America’s Test Kitchen