Preparation Steps

• Preheat oven to 350°F. Line cupcake tins with paper liners.
• In a small bowl, whisk egg whites, 0.25 cups milk, and lemon zest. Set aside.
• In a large bowl, beat butter and sugar until light and fluffy, about 3 minutes. Add dry ingredients and mix well. Gradually add egg white mixture and lemon juice, beat until smooth.
• Fill cupcake liners halfway with batter. Bake for 15 minutes or until a toothpick inserted comes out clean.
• Allow cupcakes to cool completely before frosting.
• Prepare lemon buttercream by beating softened butter with powdered sugar, lemon zest, and lemon juice until fluffy. Frost cooled cupcakes.