Chocolate Mousse Cake
["1 pkg. angel food cake", "1 sq. unsweetened chocolate", "3 c. heavy cream", "1 1/2 c. sifted confectioners sugar", "3/4 c. unsweetened cocoa", "1 tsp. unflavored gelatin", "2 tsp. vanilla", "1/4 tsp. salt", "additional chocolate and cream for decorating"]
["Prepare angel food cake according to package directions, except add grated square of chocolate to batter before pouring into tube pan.", "Bake for 30 to 40 minutes.", "Cool in pan by inverting over bottle.", "Mix the cream, sugar and cocoa; refrigerate until very cold.", "Sprinkle gelatin over 2 tablespoons cold water; let stand 5 minutes, then heat, stirring, over hot water until dissolved.", "Let cool."]
["angel food cake", "unsweetened chocolate", "heavy cream", "confectioners sugar", "unsweetened cocoa", "unflavored gelatin", "vanilla", "salt", "chocolate"]