1 cup (2 sticks) unsalted butter, at room temperature
1 cup shortening
5 cups confectioners’ sugar, sifted
1/2 cup milk or light cream
2 teaspoons vanilla extract
Grated zest of 1 lemon
In a bowl, cream together butter and shortening until light and fluffy. Scrape bowl and beaters. Add confectioners’ sugar in three stages; blend well and scrape the bowl between each addition. Add milk or cream, vanilla extract, and lemon zest; blend well.