Dark Chocolate Mousse Roulade Cake

Dark Chocolate Mousse: In large bowl over saucepan of hot (not boiling) water, melt chocolate, stirring often. Set aside.

In bowl, beat egg whites until soft peaks form; set aside. In small saucepan, bring sugar and water to boil; boil for 5 minutes or until syrup reaches soft-ball stage and candy thermometer registers 234 to 240°F (112 to 116°C) and 1/2 tsp (2 mL) syrup dropped into very cold water forms soft, pliable ball. Beating constantly, drizzle into egg whites in thin stream, beating until stiff glossy peaks form and mixture reaches room temperature.

In another bowl, whip cream. Fold half of the egg white mixture into melted chocolate; fold in half of the whipped cream. Repeat with remaining egg white mixture and cream. Cover and refrigerate for 2 hours or until chilled.

Meanwhile, line rimmed 17- x 11-inch (45 x 29 cm) baking sheet with parchment paper; set aside.

In large bowl, beat egg yolks with half of the sugar until pale and thickened, 5 minutes; beat in vanilla. In separate bowl, sift together flour, all but 1 tbsp (15 mL) of the cocoa and salt. Set bowls aside.

In separate bowl, beat egg whites until soft peaks form; beat in remaining sugar, 2 tbsp (25 mL) at a time, until stiff peaks form. Spoon one-third over egg yolk mixture; sift one-third of the flour mixture over top and fold in. Repeat twice with remaining egg white and flour mixtures.

Spread in prepared pan. Bake in centre of 400°F (200°C) oven until cake springs back when touched, about 12 minutes. Loosen edges; let cool in pan on rack for 2 minutes. Dust towel with remaining cocoa. Invert cake onto towel; peel off paper. Starting at long side, roll up cake in towel. Let cool on rack.

Unroll cake, removing towel. Spread with raspberry jam. Spread chocolate mousse evenly over cake, leaving 1-inch (2.5 cm) border uncovered on 1 long side. Starting at opposite long side, reroll gently. Cover with plastic wrap and refrigerate for 1 hour or until set. (Make-ahead: Refrigerate for up to 2 days.) To serve, sprinkle with icing sugar. Makes 12 servings.