Nonstick pan spray, optional

2 cups all-purpose flour

½ cup sugar

¼ cup packed light brown sugar

1 teaspoon cinnamon

½ teaspoon freshly grated nutmeg

¾ teaspoon baking soda

½ teaspoon fine sea salt

3 very ripe bananas

2 large eggs, at room temperature

¼ cup sour cream, at room temperature

3 ounces (¾ stick) unsalted butter, melted, plus 4 ounces (1 stick), at room temperature

1 teaspoon vanilla extract

3 ounces semisweet chocolate, chopped or ½ cup semisweet chocolate chips

8 ounces cream cheese, at room temperature

¼ cup powdered sugar

 

Preheat the oven to 350˚F. Grease a standard 12-cup muffin pan with nonstick pan spray or line with paper liners. Whisk together the flour, sugar, brown sugar, cinnamon, nutmeg, baking soda, and salt in a large bowl. Peel the bananas and, in a medium bowl, mash them using a fork. Stir in the eggs, sour cream, melted butter, and ½ teaspoon of the vanilla. Add the banana mixture to the flour mixture and stir until just combined. Divide the batter among the muffin cups. Bake for 28 to 30 minutes, or until the edges of the cupcakes start to shrink away from the pan and a toothpick inserted into the center of a cupcake comes out clean. Let the cupcakes cool in the pan for about 10 minutes. Invert onto a cooling rack and finish cooling completely.

 

Place the chocolate into a small bowl, place the bowl over a small pan of simmering water, and heat, stirring frequently, until melted. Let cool slightly. In a mixer fitted with a paddle attachment, beat the cream cheese and room temperature butter on medium until light and creamy. Add the powdered sugar and the remaining ½ teaspoon vanilla and beat until blended. Add the chocolate and continue to beat until smooth, stopping the mixer once or twice to scrape down the sides of the bowl.

 

Transfer the frosting to a pastry bag fitted with a large plain tip and pipe onto the cupcakes in a decorative manner.

 

Makes 12 cupcakes. If you don’t have a pastry bag, simply spread the frosting on the cupcakes, swirling decoratively, with a spatula. Cupcakes keep for 2 to 3 days in a tightly sealed container in a cool, dry place.