Here, this should help you:
Quick Vanilla Buttercream Frosting
Recipe courtesy Gale Gand
Ingredients
3 cups confectioners' sugar
1 cup butter
1 teaspoon vanilla extract
1 to 2 tablespoons whipping cream
Instructions
In a standing mixer fitted with a whisk, mix together sugar and butter. Mix on low speed until well blended and then increase speed to medium and beat for another 3 minutes.
Add vanilla and cream and continue to beat on medium speed for 1 minute more, adding more cream if needed for spreading consistency.
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