Press cookies, 5 tablespoons melted margarine and vanilla into 9 x 13-inch pan, up on the sides a bit.

Beat 1/2 lb. room temperature butter or margarine, powdered sugar and 2 eggs for for 15 minutes at medium speed. Spread this batter over crumb crust. Slice 2 or 3 bananas on top. Drain well a can of crushed pineapple. Spread over bananas.

Whip 2 packages Dream Whip according to direction on box. Spread this over top of bananas and pineapple. Sprinkle with chopped walnuts. Cover with foil. Refrigerate overnight.