1. Preheat oven to 350.
2. Combine the brown and white sugar in the large bowl of your Kitchen Aid mixer.
3. Then add the 2 sticks of soft butter and shortening. Beat until it is creamy.
4. Add the eggs one at a time, beating well after each addition.
5. In another large bowl, sift together the baking powder and flour 3 times.
6. Add the flour mixture alternately with the milk, beginning and ending with the flour. Add the vanilla and combine.
7. For this cake, you can use a 13 or 15-inch baking dish sprayed with Pam. In the oven melt the 1/2 stick of butter in the dish.
8. Now add your pineapple and brown sugar.
9. Pour your cake batter over pineapple mixture.
10. Bake for 1 hour 10 minutes, more or less time depending on how your oven cooks. Test cake in the middle with a wooden skewer or toothpick.