Heat oven to 350. Grease and flour two 9 or 8 inch round cake pans. In large bowl, combine cake mix, 1 cup coffee and egg whites at low speed until moistened; beat 2 minutes at high speed. Fold in chopped toffee bars. Spread batter in greased and floured pans.
Bake at 350. Bake 9 inch pans 20 to 30 minutes, bake 8 inch pans 30 to 40 minutes or until toothpick inserted in center comes out clean. Cool 10 minutes; remove from pans. Cool completely.
In medium bowl, combine sugar, chocolate syrup and cream cheese; beat until smooth. Add whipping cream and vanilla; beat until light and fluffy. Refrigerate until ready to use.
To assemble cake, slice each layer in half horizontally to make 4 layers. Drizzle each cut side with 1/4 cup coffee. Place 1 layer coffee side up on serving plate; spread with 3/4 cup frosting. Repeat with second and third cake layers. Top with remaining cake layer. Frost.