Preheat oven to 350. Grease and flour three round cake pans or grease one 9x13 baking dish.
Place all cake ingredients into a large mixing bowl and beat with an electric mixer until well blended and full combined, about two minutes.
Pour into prepared pans and bake until toothpick inserted in center comes out clean, 25-30 minutes, slightly less if you use three pans. If using round pans, allow to cool for ten minutes before turning out to cool completely. If using 9x13, allow to cool completely in pan.
For frosting, place pineapple (with juice) and pudding mix in a mixing bowl. Beat until just mixed. Add in whipped topping and beat on low speed for about one minute, until blended in. Frost cake.
Cover well and refrigerate. Best if made 2 or 3 days ahead and refrigerated before serving.
*Note: I usually make mine in a 9x13 pan just to save the trouble of fooling with the layers.