Note from the Food & Wine Test Kitchen

For an easy flourish, run a vegetable peeler along the side of a room-temperature chocolate bar to create decorative curls.

Ingredients

Cake Layers

2 1/4 cups all-purpose flour (about 9 5/8 ounces)
1 tablespoon baking powder
1/4 teaspoon fine sea salt
1 1/3 cups granulated sugar
1 cup unsalted butter (8 ounces), softened
1 tablespoon grated orange zest (from 2 large oranges)
2 1/4 teaspoons vanilla extract
3 large eggs, at room temperature
3/4 cup sour cream, at room temperature

Frosting

1 1/2 cups unsalted butter (12 ounces), softened
2 tablespoons grated orange zest (from 3 large oranges)
1/4 teaspoon sea salt
5 1/4 cups powdered sugar (about 1 pound 5 ounces)
1 1/4 cups Dutch-process cocoa
2/3 cup heavy cream, plus more as needed

Directions

Make the cake layers

Preheat oven to 350°F. Line bottoms of two ungreased 8-inch round cake pans with parchment paper; set aside. Whisk together flour, baking powder, and salt in a medium bowl. Set aside.
Beat granulated sugar, butter, orange zest, and vanilla in a large bowl with an electric mixer on medium speed until light and fluffy, 4 to 5 minutes, stopping to scrape down sides of bowl as needed. Reduce mixer speed to medium-low. Add 1 egg to sugar mixture, and beat just until combined; add one-third of flour mixture, and beat just until combined. Repeat process with remaining 2 eggs and remaining flour mixture, beating just until combined after each addition. Gently fold in sour cream just until batter is thick, smooth, and combined.
Divide batter evenly between prepared pans (about 2 1/4 cups each), spreading batter evenly using a small offset spatula. Tap bottoms of pans on counter several times to release any large air bubbles.
Bake in preheated oven until a wooden pick inserted in center of cakes comes out clean, 20 to 25 minutes. Let cakes cool in pans on wire racks 10 minutes. Remove cakes from pans; let cool completely on wire racks, 1 hour to 1 hour and 30 minutes.

Make the frosting

Beat butter, orange zest, and salt in a large bowl with an electric mixer on medium speed until smooth and creamy, about 2 minutes. Sift together powdered sugar and cocoa in a separate large bowl. Reduce mixer speed to low. Add powdered sugar mixture to butter mixture alternately with cream in 3 additions, beginning and ending with powdered sugar mixture, beating just until combined and stopping to scrape down sides of bowl as needed. (If necessary, add additional cream, 1 tablespoon at a time, to reach desired consistency.) Increase mixer speed to medium; beat until fluffy, about 2 minutes.
Trim domes of cake layers with a serrated knife to create flat surfaces. Place one cooled cake layer, trimmed side down, on a plate. Spread 1 1/2 cups frosting over cake layer; top with remaining cake layer, trimmed side down. Spread remaining frosting over top and sides of cake. Store frosted cake in an airtight container at room temperature up to 2 days or in refrigerator up to 5 days; bring to room temperature before serving.

To make ahead

Store cooled cake layers in an airtight container in a cool, dark place for up to 24 hours, or freeze layers, individually wrapped in plastic wrap and sealed in freezer-safe resealable plastic bags, up to 1 month. Defrost cakes overnight in refrigerator. Frosting can be stored in a freezer-safe, airtight container in a refrigerator for up to 1 week or in a freezer for up to 1 month; thaw in refrigerator. Let stand at room temperature until spreadable; beat with an electric mixer on medium speed until fluffy, about 2 minutes, before using.

Originally appeared in Food & Wine magazine, August 2023

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