Banana Cupcakes with Peanut Butter Frosting

1. Preheat the oven to 350 degrees F (175 degrees C). Line a 12-cup muffin pan with paper liners.

2. Whisk flour, baking powder, baking soda, and salt together in a medium bowl. Mash bananas with a fork in another medium bowl until smooth. Mix sour cream and vanilla extract into bananas.

3. Combine sugar and butter in a large bowl; beat with an electric mixer until light and fluffy, about 3 minutes. Add egg and egg yolk and beat until well blended. Add flour mixture in 2 batches, alternating with banana mixture, beating batter briefly after each addition until just blended. Scoop batter into the prepared muffin cups, adding about a generous 1/4 cup in each.

4. Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 20 minutes. Cool in the tin for 5 minutes. Transfer to a wire rack to cool completely, about 20 minutes.

5. Meanwhile, sift powdered sugar into a large bowl. Add cream cheese, butter, and peanut butter; beat with an electric mixer until smooth. Spread or pipe frosting onto the cooled cupcakes.

Cook's Notes:

After I piped the frosting on, I sprinkled cinnamon-sugar and crushed walnuts on top.

You can also make a ganache to pour over the cupcakes. Start off with 8 ounces semisweet chocolate and 8 ounces heavy cream. Break up the chocolate into a bowl. Heat the cream in a small saucepan until simmering. Pour over chocolate and let sit a minute to let the chocolate melt. Whisk gently until chocolate and cream have incorporated. Let cool slightly and pour over cupcakes.