Devil's Food Cake with Peppermint Frosting

Ingredients

• 2.7 cups all purpose flour 
• 1 tablespoon double-acting baking powder 
• 1 teaspoon baking soda 
• 14 ounces bittersweet chocolate chopped
• 12 servings bittersweet chocolate curls 
• 1 tablespoon plus light
• 3 large egg whites 
• 1 large egg yolk 
• 3 large eggs 
• 3 cups heavy whipping cream chilled divided
• 2 cups ice water 
• 0.5 teaspoon peppermint extract pure
• 1 teaspoon salt 
• 2.3 cups sugar 
• 1 cup butter unsalted room temperature (2 sticks)
• 1.3 cups cocoa powder unsweetened sifted
• 0.5 cup water 
• 12 ounces chocolate white finely chopped (such as Lindt or Perugina)

Equipment

• bowl
• sauce pan
• oven
• whisk
• hand mixer
• aluminum foil
• stand mixer
• offset spatula
• serrated knife

Directions

1. Position rack in center of oven;preheat to 350°F. Butter two 9-inch-diametercake pans with 2-inch-high sides.Dust pans with flour; tap out excess.
2. Whiskfirst 4 ingredients in medium bowl to blend.Using electric mixer, beat sugar and butterin large bowl until well blended. Beat ineggs 1 at a time, beating well after eachaddition. Beat in yolk.
3. Add cocoa and beatuntil well blended.
4. Add flour mixture in3 additions alternately with ice water in 2additions, beginning and ending with flourmixture and beating until just blended andsmooth after each addition. Divide batterbetween prepared pans; smooth tops.
5. Bake cakes until tester inserted intocenter comes out clean, about 40 minutes.Cool cakes in pans on racks 15 minutes.Invert cakes onto racks and cool completely.DO AHEAD: Can be made 1 day ahead.Wrap in foil; store at room temperature.
6. Bring cream and corn syrup to simmer inmedium saucepan.
7. Remove from heat;add chocolate and whisk until melted andsmooth.
8. Transfer to small bowl. Chill untilfirm enough to spread, about 1 hour. DO AHEAD: Can be made 1 day ahead. Beforeusing, let stand at room temperature untilsoft enough to spread, about 30 minutes.
9. Placewhite chocolate in large heatproof bowl.Bring 1 cup cream to simmer in saucepan.
10. Pour hot cream over white chocolate.
11. Let stand 1 minute; whisk until smooth.
12. Whisk in extract. Cover; chill until mixturethickens and is cold, at least 4 hours. DO AHEAD: Can be made 1 day ahead. Chill.
13. Add 2 cups chilled cream to whitechocolate cream and beat until smooth andpeaks form. DO AHEAD: Can be made 3hours ahead. Cover and chill. Rewhisk tothicken, if necessary, before using.
14. Using long serrated knife, cut eachcake horizontally in half.
15. Place 1 cake layeron platter, cut side up.
16. Spread 1/3 of darkchocolate ganache over cake. Spoon 2 cupswhite chocolate cream in dollops over cake;spread evenly to edges. Top with secondcake layer, cut side down; spread 1/3 ofganache over, then 2 cups white chocolatecream. Repeat with third cake layer, cutside up, remaining ganache, and remainingcream. Cover with fourth cake layer, cutside down. Chill while preparing frosting.
17. Combine sugar, 1/2 cup water, egg whites, and cornsyrup in large bowl of heavy-duty standmixer.
18. Whisk by hand to blend well. Setbowl with mixture over saucepan ofgently simmering water; whisk constantlywith hand whisk until mixture resemblesmarshmallow creme and ribbons form whenwhisk is lifted, 8 to 9 minutes.
19. Whisk inpeppermint extract.
20. Remove bowl from overwater and attach bowl to heavy-duty standmixer fitted with whisk attachment. Beat onhigh speed until mixture is barely warm totouch and very thick, 7 to 8 minutes.
21. Using offset spatula and workingquickly, spread frosting over top and sidesof cake.
22. Sprinkle chocolate curls over topand sides. DO AHEAD: Can be made 1 dayahead. Cover with cake dome; chill.