Iced Caramel Mousse with Bitter Chocolate Coulis

To make the sponge cake: Preheat the oven to 350 F. Lightly grease a sided baking pan and line with parchment paper. In a large bowl, beat the egg yolks and 3/4 cup of the sugar until the mixture thickens and forms a ribbon when drizzled from the spoon back over itself. Beat in the vanilla extract. In a separate bowl with a clean mixer, beat the egg whites until foamy. Add the salt and remaining 1/4 cup of sugar. Continue beating until glossy, stiff peaks form. Sift the cocoa powder and cake flour together, then add to the egg yolk mixture in three additions, folding the mixture gently together. Fold a large spoonful of the meringue into the chocolate mixture to lighten it, then fold in the remaining meringue in two more additions. Fill the prepared pan with the batter, smooth gently with a spatula, and bake 20 to 30 minutes, until a toothpick inserted in the center comes out clean. Cool in the pan for 10 minutes, then turn out on a rack and cool completely. The cake may be made a day ahead and stored, wrapped, in the refrigerator.

To make the chocolate mousse: Dissolve the gelatin in the cold water. Bring the milk to a boil over medium-high heat. Beat 1-1/2 tablespoons sugar and egg yolks until thickened. Add a large spoonful of hot milk to the egg yolk mixture and whisk gently to combine; slowly pour the egg yolk mixture into the milk and cook over medium heat until thickened enough to coat the back of a spoon. Remove from heat and stir in the chocolate, butter, and gelatin, stirring until melted.

Add a large spoonful of meringue to the chocolate mixture and whisk gently to combine. Fold in the remaining meringue in two additions. Gently fold in the whipped cream. Cover with plastic wrap and chill.

To make the caramel mousse: Heat the sugar in a heavy saucepan over medium-high heat until blue smoke appears. Immediately remove the pan from the heat as the sugar can scorch very quickly; it will already have begun to turn golden brown. Vigorously beat in the 1/2 cup of cream with a whisk, being careful as you start adding the cream as it may spatter when it hits the hot sugar. Beat the egg whites at medium speed in an electric mixer until foamy; increase the speed to high and sprinkle in the sugar, beating the whites until they stand in firm peaks. Gently fold the beaten whites into the caramel. Gently fold in the whipped cream.

To make the chocolate wrappers: Melt the chocolate in the top of a double boiler over barely simmering water. Cover a cutting board, bottom of an inverted baking sheet, or similar flat item with a piece of plastic; a square of trash bag works well. Wet the surface, place the plastic on it, and smooth with your hands until the plastic adheres to the surface and is very smooth. Blot any water that remains. Spread the warm chocolate in a very thin (less than 1/16-inch) smooth layer over the plastic using a flexible spatula. Let set until the chocolate is no longer shiny, but is still flexible.

To assemble: Place eight 3-inch diameter, 2-inch tall ring molds or pieces of PVC pipe on a baking sheet. Cut eight 3-inch circles of cake and press them into the bottoms of the molds. Cut the chocolate wrappers into 3-inch-by-9-1/2-inch strips, leaving the plastic on. The chocolate should still be warm enough to curve. Roll the plastic and chocolate into a tube and place in the molds, plastic-side out, fitting together at the seam. Put the caramel mousse in a pastry bag fitted with a large plain tip and pipe into the mold; fill it half way. Put the chocolate mousse in a pastry bag fitted with a large plain tip and fill the molds. Cover the tops with plastic wrap and chill in the refrigerator for at least 2 hours.

To make the chocolate coulis: Mix the ingredients together in a heavy saucepan and bring to a boil over medium heat. Remove from heat and let cool. Stir with a whisk to blend. Strain through a sieve and put in a squeeze bottle.

To serve: Make a large curved design to one side on each plate with the chocolate coulis. Dust the caramel mousses with cocoa powder. Put a caramel mousse mold in the center of each plate. Remove the molds and peel away the plastic. Put the caramel sauce in a squeeze bottle and pipe small lines, all oriented in one direction, across the plate. Form small quenelles of the ice cream by molding with two spoons and place one on top of each mousse. Place a tuile on top of each. Dust lightly with confectioner’s sugar and garnish with hazelnuts.