- In a bowl, beat the egg whites and cream of tartar with an electric mixer until soft peaks form. Gradually add the sugar, beating until the peaks are very stiff, about 6 minutes. Add 375 ml (1 1/2 cups) raspberries and continue beating for 1 minute. Refrigerate.
- To serve, spoon the mousse into 6 dessert dishes. Garnish with fresh raspberries and serve with cookies.