bittersweet chocolate, chopped
Step by step
Put chocolate in blender jar of the KitchenAid ARTISAN Power Plus Blender. Combine milk, cream, sugar and salt in small saucepan over medium heat, stirring, until mixture is steaming hot and sugar is dissolved for about 2 minutes. Do not allow mixture to boil. Pour hot milk mixture over chocolate in blender jar and leave to stand for 2 minutes.
Secure lid and turn dial to Speed 1. Blend, slowly increasing speed to medium (Speed 5 or 6), until thickened and very smooth for about 30 seconds. Add egg whites and vanilla and blend on medium-high speed (Speed 8) until thick and frothy for about 2 minutes.
Divide mousse evenly among six custard cups or ramekins. Cover with plastic wrap and refrigerate until chilled and firm for about 2 hours, before serving. Mousse will keep in refrigerator for up to 3 days.
Chocolate-raspberry mousse: Add 2 tablespoons seedless raspberry jam to blender jar with egg whites and vanilla. Proceed as directed. Chocolate-orange mousse: Add finely grated peel of 1 orange to blender jar with chocolate. Proceed as directed.