Preheat the oven to 350 degrees and line a 12-cup muffin tin with paper liners.

In a medium bowl combine the flour, baking powder, baking soda, and salt. Use a whisk to combine them. In a separate medium bowl add the melted butter and the sugar. Stir to combine (will be gritty). Add the egg whites, yogurt, milk, and vanilla extract to the sugar mixture and stir to combine. Add the flour mixture all at once and stir until just incorporated. The batter will be thick.

Divide the batter evenly among the 12 lined cups. Bake for around 20 minutes until a toothpick inserted into the center of a cupcake comes out clean. Remove from the oven. Let the cupcakes rest for 5 minutes before removing them from the pan. Allow to cool before frosting.

Add the butter to the bowl of your stand mixer. Mix on medium speed with the whisk attachment until the butter is light and fluffy, 3 to 5 minutes, Add cream, extracts, salt, and 2.5 cups of the powdered sugar. Mix on low until combined and then increase speed to medium and whip for 3 to 5 minutes. Add the icing 1/2 to a 1/4 cup at a time to until you reach the desired consistency.

The constancy of the icing is important if you are going to pile it high on a cupcake. It should be a medium consistency. If you mix the batch of icing with a metal teaspoon (the kind you use for dinner) it should stand up straight in the middle of the bowl when it is in the icing. So, you should be able to stir it with a spoon by hand but it should also be sturdy enough to hold the spoon up. If the icing is too thick, add a little cream. If it needs to be a little thicker add a 1/4 cup of powdered sugar and whip to combine until it's sturdy enough.

Place in an icing bag and pipe on the cool cupcakes with tip 2A