Magnolia Bakery Vanilla Buttercream
From More From Magnolia: Recipes from the World Famous Bakery and Allysa Torey's Home Kitchen
1 cup (2 sticks) unsalted butter, softened
6 to 8 cups confectioners' sugar
1/2cup milk
2 teaspoons pure vanilla extract
In the bowl of an electric mixer fitted with the paddle attachment, combine butter, 4 cups sugar, milk, and vanilla. Beat on medium speed until smooth and creamy, 3 to 5 minutes. Gradually add remaining sugar, 1 cup at a time, beating for about 2 minutes after each addition, until icing reaches desired consistency; you may not need to add all the sugar. Store in an airtight container for up to 3 days.
Makes enough buttercream for about 2 dozen cupcakes.
This is the exact recipe I've been making my whole life, passed from my grandmother to my mother to me. Whenever I go to Magnolia, I realize that the secret to their cupcakes being so delicious they make everything homemade the way I'd make it myself - nothing artificial. And judging by the lines outside there everyday, everyone agrees how good they are.
My only additional suggestion would be to let the chill get off the milk before adding it. It seems to blend better when not cold right out of the refrigerator.