White Chocolate Cupcakes with Pistachio Buttercream

INGREDIENTS

FOR THE CUPCAKES:

5 oz

white chocolate, finely chopped

1 1/2 cups

all-purpose flour

1 tsp

baking powder

1/2 tsp

salt

1 cup

whole milk

1 tbsp

vanilla extract

2/3 cup

granulated sugar

4 tbsp

butter, room temperature

large eggs, room temperature

FOR THE BUTTERCREAM:

2 sticks

butter, room temperature

egg whites, room temperature

1/4 tsp

cream of tartar

1 cup

powdered sugar

1/2 cup

granulated sugar

1/3 cup

pistachios, very finely ground (almost paste-like)

drops green food coloring