Prep 20 mins
Cook 35 mins
- 1⁄2 cup unsalted butter, softened, plus additional
- unsalted butter, for greasing
- 1 1⁄2 cups all-purpose flour, plus additional
- all-purpose flour, for dusting
- 2 teaspoons baking powder
- 3⁄4 teaspoon cinnamon
- 1⁄2 teaspoon salt
- 1⁄4 teaspoon freshly grated nutmeg
- 1⁄4 teaspoon ground cloves
- 1⁄4 teaspoon ground allspice
- 2⁄3 cup apple cider (not filtered)
- 2 teaspoons fresh lemon juice
- 1 cup packed light brown sugar
- 3 large eggs, at room temperature for 30 minutes
- 3⁄4 cup sugar
- 3 tablespoons cornstarch
- 1⁄8 teaspoon salt
- 3⁄4 cup apple cider (not filtered)
- 1 1⁄4 cups unsalted butter, softened
- Make cake: Put oven rack in middle position and preheat oven to 350°F Butter 2 (8- by 2-inch) round cake pans and dust with flour, knocking out excess.
- Whisk together flour (1 1/2 cups), baking powder, cinnamon, salt, nutmeg, cloves, and allspice in a medium bowl.
- Combine apple cider and lemon juice in a small measuring cup.
- Beat butter in a large bowl with an electric mixer at medium-high speed until light and fluffy, then add brown sugar and beat until combined. Add eggs 1 at a time, beating well after each addition (mixture will look curdled).
- Reduce speed to low and add flour mixture and cider mixture alternately in 3 batches, beginning and ending with flour mixture and mixing until just combined.
- Divide batter between cake pans (batter will form a thin layer) and rap pans on work surface once to release any large air bubbles.
- Bake cake layers until they begin to pull away from sides of pans and a wooden pick or skewer inserted in center of each cake layer comes out clean, 25 to 30 minutes.
- Cool cake layers in pans on racks 5 minutes, then run a thin knife around edge of each layer and invert layers onto racks. Cool completely, at least 1 hour.
- Make buttercream while cakes cool: Whisk together sugar, cornstarch, and salt in a 2-quart heavy saucepan.
- Whisk in cider, then bring to a boil over moderate heat, whisking constantly, and boil, whisking constantly, 1 minute (mixture will be very thick).
- Transfer to a metal bowl and set in a larger bowl of ice and cold water, then stir occasionally until cool, about 30 minutes.
- Beat butter in a large bowl with cleaned beaters at medium-high speed until light and fluffy, then add one third of cider mixture and beat until incorporated.
- Add remaining cider mixture and continue beating until smooth.
- When cakes are cool, arrange 1 layer flat side up on a flat serving plate or cake stand and spread top with 3/4 cup buttercream. Top with remaining cake layer flat side up.
- Frost top and side of cake with remaining buttercream. Chill 2 hours before serving (to firm up buttercream).