Prepare and bake cake according to package directions.
In a small saucepan, mix together the pineapple, including juice and sugar and bring to a boil.
When cake is done, remove from oven and pour the pineapple mixture over the top of the hot cake, spreading evenly. Place in refrigerator to cool.
Once cool, top with the sliced bananas.
Prepare the instant pudding according to package directions and spread over the bananas.
Spread the whipped topping over the pudding. Sprinkle the chopped pecans over the whipped topping. Sprinkle the coconut over the pecans.
Store in the refrigerator.Makes 18