How to Make It
Heat oven to 350° F and line a standard 12-cup muffin tin with paper liners. Combine the flour, baking powder, cinnamon, cloves, and salt in a medium bowl.
Combine the brown sugar, vegetable oil, molasses, egg, and egg yolks in a large bowl. Stir in the mashed bananas, sour cream, and ginger.
Gently fold the dry ingredients into the wet ingredients until just combined.
Divide the batter between the prepared cups. Bake until a toothpick inserted into the center of the cakes comes out with just a few moist crumbs, 22 to 25 minutes. Transfer cupcakes to a rack to cool completely.
Prepare the frosting. Whisk together the confectioners’ sugar, milk, vanilla, and salt in a large bowl. Dip the top of each cupcake in the glaze. Let the cupcakes stand at room temperature until the glaze sets. Top with a ginger cookie, if desired.