1 cup (2 sticks) unsalted butter, room temperature
12 ounces cream cheese, room temperature
1 pound (4 cups) confectioner's sugar, sifted
1/4 teaspoon pure vanilla extract
With an electric mixer on medium-high speed, beat butter and cream cheese until fluffy, 2 to 3 minutes. Reduce speed to low. Add sugar, 1/2 cup at a time, and then vanilla, and mix until smooth and combined, scraping down sides of bowl as needed.