Preheat oven to 350 degrees F. Line a regular muffin tin with muffin liners.
In a medium bowl, mix flour, baking powder, baking soda and salt. This is the dry mixture.
In a stand mixer bowl, mix butter, sugar, milk and vanilla. Add the dry mixture and combine until evenly mixed. You can wash the bowl or use another bowl with a handheld mixture to whip the egg whites.
Mix egg whites until soft peak. Fold into the batter until combined.
Using an ice cream scoop, scoop out batter into the prepared muffin tins. Bake for about 15-18 minutes. Let cool before putting on the frosting.
White Chocolate Frosting
Melt the chocolate in the microwave for 20 seconds. If not melted yet, add another 10 seconds each time until completely melted.
In a stand mixer bowl, beat butter and cream cheese. Add the white chocolate and vanilla, mix again for another minute.
Add the powdered sugar and beat until its light and fluffy. Add milk a tablespoon at a time until it reaches the right consistency.
Place in a piping bag and pipe on the cooled cupcakes to make the base of the nest.