Grease & flour tube or bundt cake pan. Melt margarine. Stir in frosting mix & oatmeal & set aside, Beat bananas, sour cream & eggs. Stir in dry cake mix & beat for 2 minutes. Put 2 cups of this batter into a baking dish. Sprinkle 1 cup of crunch mix over batter. Repeat layers. End with crunch on top. Bake at 350° for approximately 1 hour.