Preheat oven to 350 degrees F and line a muffin tin with 12 cupcake liners (I used Reynolds foil lined cupcake liners).
In a mixing bowl, whisk flour, baking powder and salt together and set aside.
Cream butter and sugar together for 2-3 minutes in the bowl of an electric mixer using the paddle attachment. Mix in the vanilla and egg and then mix in the egg white. Alternate mixing in the flour mixture and the whole milk in 3 batches. Mix until just combined (scrape sides of bowl as needed).
Spoon batter into cupcake liners (3/4 full) and bake for 17-20 minutes, until toothpick comes out clean. Let cupcakes cool in pan for 5 minutes and then remove to a cooling rack.
Meanwhile, mix the sweetened condensed milk, half & half, and coconut milk together.
Use a skewer to poke lots of holes in the top of each cupcake. Place the cooling rack of cupcakes on top of a rimmed cookie sheet (to catch drippings) and spoon milk mixture over the top of each cupcake. Refrigerate 30 minutes and then spoon the remaining mixture over the top.
Refrigerate at least 1 hour (to allow milk to soak in) before adding topping and serving.
For the Topping:
With an electric mixer, beat whipping cream and sugar just until stiff peaks form. Dollop onto cupcakes and then sprinkle with coconut flakes. Top with a cherry and serve. (Keep refrigerated until ready to serve.)