1 pkg. yellow cake mix
1 (20 oz.) can crushed pineapple
3/4 c. sugar
3 tbsp. cornstarch

Bake cake mix according to instructions on box in 2 round cake tins. Mix pineapple, sugar, and cornstarch together and boil for 1 minute. Let cake cool. Take a piece of thread and pull through middle of each cake. Put pineapple mixture between the layers of cake concluding with layer of cake on top. Frost with Cool Whip.