Chocolate Toffee Mousse Cake Recipe

Prepare

Preheat oven to 350°F (175°C). Grease and line the bottom of a 9-inch (23 cm) springform pan with parchment paper; lightly grease sides.

Mix dry ingredients

In a bowl sift together all-purpose flour, cocoa powder, baking powder and salt; set aside.

Combine wet ingredients

In a separate bowl whisk eggs and granulated sugar until slightly pale. Add milk, vegetable oil and vanilla extract and whisk until combined.

Combine and bake

Fold dry ingredients into the wet mixture just until combined (do not overmix). Pour batter into prepared springform and smooth top. Bake 18–22 minutes or until a toothpick inserted in center comes out with a few moist crumbs. Remove from oven and cool in pan 10 minutes, then release sides and cool completely on a rack. Once cool, trim top if needed to make an even layer.

Melt chocolate

Place chopped bittersweet chocolate in a heatproof bowl. Heat 1/2 cup of the heavy cream until just simmering and pour over chocolate. Let sit 1 minute, then stir until smooth. Stir in unsalted butter, vanilla extract and salt. Allow to cool to room temperature but still pourable.

Whip cream

Whip remaining 1.5 cups heavy cream with 2 tablespoons sugar to soft-medium peaks.

Fold to make mousse

Fold about one-third of whipped cream into the cooled chocolate to lighten it, then gently fold in remaining whipped cream until homogeneous and airy. Do not overfold. Chill briefly (10–15 minutes) if mousse needs to firm slightly before assembling.

Make toffee

Line a small baking sheet with parchment. In a medium skillet or heavy saucepan over medium heat add 1/2 cup sugar and corn syrup (if using). Stir gently until sugar melts and turns amber (watch closely to avoid burning). When it reaches a deep golden color, remove from heat and quickly stir in butter (be careful, it will bubble) then slowly add warm heavy cream and salt; stir until smooth.

Combine crunch

Immediately stir in chopped nuts and crushed wafer cookies until evenly coated. Spread mixture thinly on prepared sheet and allow to cool and harden completely. Once set, break into small pieces (about 1/4-inch to 1/2-inch) for sprinkling between cake layers and for garnish.

Cook berries

In a small saucepan combine mixed berries, granulated sugar, grated ginger, lemon juice and water. Bring to a gentle simmer over medium heat and cook 6–8 minutes, stirring occasionally, until berries break down and syrup thickens slightly.

Blend and strain

Remove from heat and let cool slightly. For a smooth coulis, puree mixture with an immersion blender or in a countertop blender until smooth, then strain through a fine mesh sieve to remove seeds and fibrous ginger. Taste and adjust sweetness or acidity with more sugar or lemon if desired. Chill until ready to serve.

Layer cake

Place the cooled sponge back into the springform pan base or use a cake ring on a serving plate. Spread about one-quarter of the mousse evenly over the sponge. Sprinkle half of the toffee crunch pieces evenly over the mousse, pressing lightly so they adhere. Add another quarter of mousse to cover the crunch and smooth. If you have enough sponge, you may add a second thin sponge layer; otherwise continue building so that final top is mousse. Finish by spreading remaining mousse smoothly over top.

Chill

Refrigerate the assembled cake for at least 3 hours, preferably overnight, to allow mousse to set and flavors to meld.

Unmold and decorate

Run a thin knife around the pan sides to loosen and remove the springform. Dust top lightly with cocoa powder. Scatter remaining toffee crunch pieces around the edge and over the top. Garnish with fresh berries and chocolate shavings.

Serve with coulis

Slice the chilled cake with a hot, dry knife (wipe blade between slices). Serve slices with a drizzle or spoonful of chilled berry-ginger coulis alongside.