Chocolate Mousse Cake

Instructions

1. 1. Preheat oven to 350°F and grease a 9-inch springform pan. Remove ring, place parchment on bottom plate, and close ring with paper extending up sides.
2. 2. In medium bowl, whisk together flour, cornstarch, cocoa powder, baking soda, baking powder, and salt. Set aside.
3. 3. In large bowl, whisk together granulated sugar, brown sugar, and oil until mixture resembles wet sand.
4. 4. Whisk in eggs and vanilla, then sour cream.
5. 5. Add dry ingredients and mix until halfway combined. Pour in hot coffee and mix until smooth. Batter will be very thin.
6. 6. Pour batter into prepared pan and bake 25-30 minutes until toothpick comes out with few moist crumbs.
7. 7. Cool cake completely, then remove ring and level top with cake leveler or knife. Replace clean ring around cake.
8. 8. Line pan with acetate sheet, sliding between cake and pan sides.
9. 9. For cake soak: Stir together hot coffee and cocoa powder. Spoon evenly over cake surface.
10. 10. For mousse: Melt both chocolates in double boiler until smooth. Cool slightly, then whisk in egg yolks one at a time.
11. 11. Sprinkle gelatin over 3 tbsp water in small bowl. Let bloom.
12. 12. Heat ¾ cup cream until steaming. Whisk in bloomed gelatin until dissolved.
13. 13. Pour half the cream mixture into chocolate, whisk smooth, then add remaining cream. Mixture should be glossy like pudding.
14. 14. Whip remaining 1 cup cream to stiff peaks. Set aside in clean bowl.
15. 15. In clean bowl, whip egg whites and cream of tartar. When foamy, gradually add sugar and whip to soft peaks.
16. 16. Fold whipped cream into chocolate mixture, then fold in meringue until no streaks remain.
17. 17. Pour mousse over cake and refrigerate at least 4 hours, preferably overnight.
18. 18. For ganache: Remove cake from pan and peel off collar. Place chopped chocolate in bowl.
19. 19. Microwave cream until bubbling, pour over chocolate, let sit 3 minutes, then whisk until smooth.
20. 20. Pour ganache in center of cake, spread to edges allowing drips. Chill 30 minutes before serving.