Chocolate Cake with Mousse Filling and Silky Ganache Finish

Every chocolate lover should have a trusted chocolate cake recipe that is consistently delicious. This one is reliable, rich and sure to become a favorite.

Ingredients

Chocolate cake base (two 9-inch round cakes)

• Cake flour: 2 cups + 4 tbsp
• Light brown sugar: 1½ cups
• Honey: ½ cup
• Natural cocoa: ¾ cup, plus extra for dusting
• Baking powder: 2 tsp
• Baking soda: 1½ tsp
• Salt: 1 tsp
• Espresso powder: 2 tsp
• Sour cream: 1 cup
• Vegetable oil: ½ cup
• Large eggs: 2
• Orange extract: 2 tsp
• Boiling water: 1 cup

Chocolate mousse (with gelatin, no eggs)

• Heavy whipping cream: 1¾ cups
• Semi-sweet chocolate chips: 8 oz
• Unsalted butter: 4 tbsp
• Vanilla extract: 1 tbsp
• Unflavored gelatin: 1 tsp
• Sugar syrup: 1 cup
• Chocolate ganache (made with 6 oz dark chocolate, 85% cacao): about 3 cups

Instructions

Chocolate cake base

1. Preheat the oven to 350°F (175°C).
2. Grease and dust two 9-inch cake pans with cocoa, coating the sides well.
3. In a heatproof bowl, combine the cocoa powder and espresso with the boiling water and let it bloom for a few minutes.
4. In a large bowl, sift together cake flour, sugar, baking powder, baking soda and salt.
5. In a separate bowl, whisk the eggs, then add oil, honey, sour cream and orange extract; mix until smooth.
6. Pour the wet ingredients into the dry ingredients and mix gently with a hand mixer until just combined. Avoid overmixing.
7. If needed, finish combining with a silicone spatula using a folding motion.
8. Divide the batter between the two prepared pans and bake 35–40 minutes, or until a cake tester comes out clean.
9. Cool cakes in the pans for 20 minutes, then transfer to a wire rack to cool completely. If not assembling immediately, wrap and refrigerate.

Chocolate mousse

1. Sprinkle the gelatin over ¼ cup cold cream and let it bloom for 10 minutes.
2. Melt the chocolate with butter and vanilla in a double boiler. Let it cool to around room temperature.
3. Gently warm the gelatin mixture in a hot water bath until dissolved, then stir it into the chocolate.
4. Whip the remaining cream to medium-stiff peaks.
5. Fold the gelatin-chocolate mixture into the whipped cream, taking care not to overwork the mousse.
6. Cover and chill in the refrigerator for at least 4 hours or overnight to set.

Assemble the cake

1. Bring the cake layers to room temperature. Work in a cool room to keep the mousse stable.
2. Brush each cake layer with sugar syrup (one part sugar to two parts water works well).
3. Allow the syrup to soak in for about 30 minutes.
4. Place one cake layer on a cake board or serving plate.
5. Remove the mousse from the fridge. Dip an icing spatula in hot water, scrape off excess, then spread a generous layer of mousse over the cake. Repeat until all mousse is used, smoothing the top evenly.
6. Place the second cake layer on top and press gently so the mousse peeks slightly from the sides.
7. Spread chilled, spreadable ganache over the top and sides to cover the cake completely.
8. Let the assembled cake rest for about 40 minutes before slicing to ensure clean cuts.