Prepare cake mix according to package directions. Bake in two 9x 1 1/2 in round cake pans; cool. Meanwhile, stir ice cream to soften;quickly stir in 1/2 cup of the concentrate and the food coloring. Spread evenly in foil-lined 9x1 1/2 in round cake pan. Freeze 2 or 3 hours ortill firm. Place cake layer on serving plate; top with icream layer, then with second cake layer. Beat cream with remaining concentrate and the sugar till stiff. Frost sides and top of cake; return to freezer at least 1 hour or till served.