Combine:

1 box cake mix (yellow or white with pudding in it)
1 medium can crushed pineapple
1 cup sugar
1 box instant vanilla pudding (or pineapple cream)
1 container Cool Whip

1 cup flaked, sweetened toasted coconut

Prepare yellow cake mix as directed using a greased 13 by 9 by 2-inch pan and bake for 30 to 35 minutes. While cake is baking, combine the pineapple and 1 cup of sugar in a saucepan, and bring to a boil over medium heat stirring constantly. Remove from heat and allow to cool slightly.

Remove cake from oven and using a fork or straw, pierce holes into cake. Pour pineapple mixture over hot cake and set aside.

Prepare pudding according to package directions. Spread pudding over cake and refrigerate until thoroughly chilled. Cover top of cake with Cool Whip and sprinkle toasted coconut on top.