Lemon Cupcakes

Directions

1. 1
   Preheat the oven to 350 degree F. Line about 15 muffin cups with paper liners and set aside.In a medium bowl, combine flour, baking powder, baking soda, and salt; set aside.In a large bowl, beat the butter with an electric mixer on medium speed for 30 seconds.
2. 2
   Add the granulated sugar and vanilla; beat until well mixed.
3. 3
   Add the egg and egg yolk and mix well.
4. 4
   Add the 1/3 of the flour mixture and mix.
5. 5
   Add 1/2 of the sour cream and mix again.
6. 6
   Add another 1/3 of the flour mixture, stirring until combined.
7. 7
   Add the final 1/2 cup of the sour cream and after mixing, add the final 1/3 of the flour.
8. 8
   Mix just until combined. Stir in the 2 teaspoons lemon zest. The batter will have a thick consistency.Spoon about 1/4 cup of the batter into each prepared muffin cup filling between 1/2 and 2/3 full.
9. 9
   Bake the cupcakes for 16-18 minutes until a toothpick inserted in the center comes out clean. Cool completely on a wire rack before frosting.For the frosting, in a medium bowl, beat the butter, powdered sugar and lemon juice together until light and fluffy, about 1-2 minutes with an electric mixer (stand mixer or handheld).
10. 10
    Mix in the vanilla and add 1-2 teaspoons of milk to adjust the consistency, if necessary. It should be creamy and spreadable. Stir in the 1 teaspoon lemon zest. Dollop a tablespoon or two of the frosting on each cupcake and spread until smooth. Top with a few sprinkles of fresh lemon zest, if desired.