Make in a 9"x13" pan a yellow butter cake mix according to directions. Meanwhile, mix 1 large package vanilla instant pudding mix with 3 cups milk. Crumble the cooled cake in a large glass punch bowl. Pour pudding over cake. Pour 1 large can crushed pineapple plus juice over pudding. Top with 1 can cherry or strawberry pie filling. Top with 1 large container Cool Whip. Chill several hours before serving. Will serve at least 16.