Cake: Preheat oven to 350F. Pour cake mix into large bowl, add water and mix. Add eggs and margarine and mix well until batter is smooth. Pour equal amounts into three 9-inch cake pans sprayed with Pam. Bake for 15-20 minutes.
Filling/Frosting: Put drained pineapple into two quart bowl. Add Cool Whip and stir. Add instant pudding and stir until mixture thickens. Add coconut and stir until coconut is even throughout mixture. Use as filling between cooled layers and for frosting on top and sides of cake.
Cajun Country -- New Iberia, Louisiana