- 1 cup (8 oz/250 g) unsalted butter, at room temperature
- 2 egg yolks
- 1 tbsp vanilla extract
- 1/4 tsp salt
- 2 cups (8 oz/250 g) confectioners' sugar
- Using an electric mixer on high speed, beat the butter until fluffy, 3-4 minutes. Add the egg yolks and beat until fluffy. Beat in the vanilla, salt, and confectioners' sugar. Remove the cupcakes from the pan and spread the buttercream evenly over the top of each cupcake.