Servings: About 3 cups, enough for 1 dozen cupcakes

3/4 cup butter, room temperature ¾ cup butter, room temperature
1 cup mascarpone cheese 1 cup mascarpone cheese
3 cups powdered sugar 3 cups powdered sugar
1 teaspoon pure vanilla 1 teaspoon pure vanilla

In a stand mixer fitted with a paddle attachment, cream the butter on high speed for about 2 minutes. Add the mascarpone and beat again until well combined. Scrape down the sides of the bowl.
Turn the mixer speed to low and slowly add the icing sugar. Mix until well combined. Scrape down the sides of the bowl. Add the vanilla and beat again.
Turn the mixer speed to high and beat for another 5 minutes, or until the buttercream is light and fluffy.