Start by pouring melted butter into your glass pie plate. Next, sprinkle on an even layer of brown sugar. Arrange the pineapple slices and maraschino cherries on top.
In a large bowl whisk together flour, baking powder, and salt. Set aside. In another large bowl cream together butter, shortening, granulated sugar, and brown sugar using a hand mixer. Mix in eggs and vanilla extract. Gradually mix the dry ingredients into the wet ingredients while alternating with the milk and heavy whipping cream just until combined and the mixture is fluffy. Spoon the batter evenly over the topping and spread it into an even layer.
Bake the cake in preheated 325 F. oven for 40 minutes. Cover loosely with tented foil and bake for another 30-35 minutes or until a toothpick inserted into the center comes out clean.
Let the cake cool on a wire rack for 15 minutes (no longer than that) and invert it onto a cake stand or serving platter.
Let cool for about 5 more minutes. Slice and serve warm. Vanilla ice cream or homemade whipped cream works perfectly with this!