Active Time

　　1 hour

　　Total Time

　　3 hours 20 minutes (including chilling time)

　　This tender buttermilk cake with rich orange cream-cheese frosting is sure to become your go-to for any festive occasion. The recipe can easily be adjusted to suit any party need: Make this single layer cake for birthdays, bake it as a sheet cake for backyard barbecues, or as a double-layer cake for even bigger celebrations.

　　

Ingredients

Makes 1 (10-inch) cake

　　

For the Buttermilk Cake:

Nonstick vegetable oil spray

　　2 cups cake flour

　　1 teaspoon baking powder

　　1/2 teaspoon baking soda

　　1/4 teaspoon kosher salt

　　3/4 cup (1 1/2 sticks) unsalted butter, room temperature

　　1 3/4 cups granulated sugar, divided

　　4 large eggs, separated

　　1 teaspoon vanilla extract

　　1 cup buttermilk

　　

For the Vanilla Syrup:

1/4 cup granulated sugar

　　1 vanilla bean, split lengthwise

　　

For the Orange Cream-Cheese Frosting:

2 (8-ounce) packages cream cheese, chilled

　　10 tablespoons unsalted butter, room temperature

　　1 teaspoon finely grated orange zest

　　1 tablespoon fresh orange juice

　　1 teaspoon vanilla extract

　　3/4 cup powdered sugar, sifted

　　

For assembly:

6 ounces raspberries, divided

　　Edible flowers (for garnish; optional)

　　

Special Equipment:

A 10-inch round cake pan

　　

Bake the Buttermilk Cake:

Step 1

Place a rack in middle of oven; preheat to 350°F. Lightly coat cake pan with nonstick spray and line bottom with parchment paper. Whisk flour, baking powder, baking soda, and salt in a medium bowl; set aside.

　　

Step 2

Using an electric mixer on medium-high speed, beat butter and 1 1/2 cups granulated sugar in a large bowl, scraping down sides of bowl as needed, until light and creamy, about 5 minutes. Add egg yolks in 2 additions, scraping down bowl after each. Beat in vanilla.

　　

Step 3

Reduce mixer speed to low, then add dry ingredients in 2 additions alternately with buttermilk in 2 additions, scraping down sides of bowl as needed.

　　

Step 4

Using electric mixer on medium speed, beat egg whites in another large bowl until soft peaks form, 2–3 minutes. Slowly add remaining 1/4 cup granulated sugar and continue to beat until stiff, glossy peaks form, about 3 minutes more. Fold half of the egg whites into flour mixture, then gently fold in remaining egg whites.

　　

Step 5

Scrape batter into prepared pan; smooth surface. Bake, rotating pan halfway through and covering with foil during the last 15 minutes of baking, until golden brown, firm to the touch, and a tester inserted into the center comes out clean, 45–50 minutes. Transfer pan to a wire rack and let cake cool.

　　

Make the Vanilla Syrup:

Step 6

Combine granulated sugar and 1/4 cup water in a medium saucepan. Scrape in vanilla seeds, add pod, and stir to combine. Bring to a boil, cover, and steep at least 15 minutes. Set aside to cool. Discard pod before using.

　　

Make the Orange Cream-Cheese Frosting:

Step 7

Using electric mixer on medium-high speed, beat cream cheese and butter in a large bowl until smooth, about 1 minute. Beat in orange zest, orange juice, and vanilla. Reduce mixer speed to medium and beat in powdered sugar, scraping down bowl as needed, until light and fluffy, 2–3 minutes.

　　

Assemble the cake:

Step 8

Run a knife around sides of cooled cake and invert onto a wire rack; remove parchment.

　　

Step 9

Spread 1 Tbsp. frosting in the center of a platter. Place cake, top side down, in the center. Using a pastry brush, brush 3 Tbsp. vanilla syrup over top of cake; reserve remaining syrup for another use. Spread 1 cup frosting evenly over top and sides to create a crumb coat. Chill 30 minutes to let frosting set. Frost top and sides, swirling decoratively; reserve remaining frosting for another use.

　　

Step 10

Chill at least 30 minutes or up to overnight to let frosting set. Before serving, top cake with 3 oz. raspberries and edible flowers, if using. Serve remaining 3 oz. raspberries alongside.

　　

Do Ahead

Step 11

Cake can be made 3 days ahead; wrap tightly in plastic and chill, or freeze up to 2 weeks. Syrup can be made 5 days ahead; store in an airtight container and chill. Frosting can be made 3 days ahead; cover with plastic wrap, pressing directly on surface, and chill. Bring to room temperature before using.