Pineapple Cake - cooking recipe

Ingredients

1 box Betty Crocker Super Moist cake mix
1 tall can crushed pineapple (unsweetened)
3 Tbsp. cornstarch
1 c. sugar
1/2 stick butter

Preparation

Bake cake according to package directions.
Cook pineapple, sugar and cornstarch until thick.
Remove from heat and add butter.
Cool completely before putting on cake.
I double this recipe because I like the cake to be gooey.