Flourless Chocolate Cake

1. Preheat oven to 300°F. Grease 9-inch springform pan; line bottom of pan with parchment paper.

2. Melt chocolate and margarine in small heavy saucepan over low heat, stirring frequently; cool. Dissolve espresso powder in hot water in small bowl.

3. Place 6 egg whites in large bowl; set aside. Beat egg yolks in medium bowl with electric mixer at high speed about 5 minutes, or until pale yellow in color. Add 1/3 cup sugar; beat about 4 minutes, or until mixture falls in ribbons from beaters. Slowly beat in melted chocolate mixture and espresso mixture at low speed just until blended. Beat in cocoa and vanilla just until blended.

4. Add salt to egg whites; beat at high speed 2 minutes or until soft peaks form. Beat in remaining 1/3 cup sugar until stiff peaks form. Stir large spoonful of egg whites into chocolate mixture. Fold chocolate mixture into egg whites until almost blended. Spoon batter into prepared pan.

5. Bake 1 hour, or until cake begins to pull away from side of pan. Cool on wire rack 10 minutes; run thin spatula around edge of cake. Carefully remove side of pan. Cool completely. Invert cake; remove bottom of pan and paper from cake. Cover and refrigerate at least 4 hours. Serve chilled with whipped topping, raspberries and mint, if desired.