Preheat oven to 350 degrees F.
Beat eggs in a mixing bowl until becomes fluffy, it would take 5 min. Don’t over beat eggs otherwise foam and liquid will separate.
Add sugar and start beating again until mixture gets creamy texture.
Sift together baking powder and flour and then gradually mix it into the egg mixture using flat spatula so that batter should not settle down at the bottom otherwise your sponge may become hard.
Now fold the batter with crushed pineapple and coconut flakes.
Pour the batter into the greased and dusted baking pan of rectangular pan. Place the pan in oven for 20-30 min until become done.
Meanwhile prepare frosting for the cake, for that mix pineapple and vanilla pudding mix and beat until it gets thick and then fold it evenly with the cool whip.
When the sponge is ready cool it to room temperature cut it horizontally from the center. Now do the icing on one of the piece of cake as filling and place another piece onto the frosting.
Cover the whole cake with the remaining frosting and then decorate with pineapple chunks and coconut flakes.