Spring is just around the corner, but we’re still a long way off from fresh berries and stone fruit. While I’m still using citrus in almost everything, I realized today that there is always one fruit hanging out on my counter, no matter the season: bananas! of course! I use it in quick bread quite often, but banana cupcakes topped with banana buttercream is quite a treat.
Makes 14-16 cupcakes, cupcake batter adapted from The Food 52 Baking Book
- 1/2 cup unsalted butter, room temperature
- 1 1/2 cups granulated sugar
- 2 large eggs, separated
- 2 bananas, mashed
- 1 teaspoon pure vanilla extract
- 1/2 cup buttermilk
- 1 2/3 cups pastry flour
- 1 teaspoon baking soda
- 1/4 teaspoon baking powder
- 1/2 teaspoon salt
- 3 super ripe bananas, mashed
- 1 tablespoon butter
- ¼ cup granulated sugar
- ½ teaspoon yellow food coloring
- 3-4 sticks unsalted butter, room temperature (room temperature) (see note)
- 1 teaspoon pure vanilla extract
- 1 tablespoon black strap rum (optional)
- Pinch salt
- 2 cups confectioner’s sugar
- ¼-1/2 cup heavy cream (see note)
For the cupcakes
- Heat the oven to 350° F, and adjust an oven rack to the middle position. Line two muffin tins.
- In a medium bowl, whisk together the flour, baking soda, baking powder, and salt.
- In the bowl of a stand mixer fitted with the paddle attachment, beat the butter on medium until creamy. Add the sugar, and then beat again until light and fluffy, 3-5 minutes. Add the egg yolks one at a time, and mix until incorporated, scraping down the bowl as needed. Stir in the bananas, vanilla, and rum, then stir in the buttermilk until well combined.
- Add the flour mixture to the batter, and stir gently until just combined.
- Put the egg whites in a clean, dry bowl of a stand mixer fitted with the whisk attachment. Whisk until soft peaks form. Gently fold the egg whites into the batter.
- Fill the muffin wells a little over half way with batter (any more and the cupcakes will bake up high and flatten onto the top of the pan), and bake for 14-20 minutes, or until a toothpick inserted into the center of the cakes comes out with only a few dry crumbs.
- Move the pans to a wire rack and let the cupcakes cool in the pans for 10 minutes. Remove the cakes from the pans and let them finish cooling on the wire rack. Wait until completely cool before frosting. Top with banana buttercream.
Note: If you don’t have pastry flour, you can use all-purpose. Omit 2 tablespoons of the flour once measured, and then add 2 tablespoons of cornstarch, whisking well to combine.
For the buttercream
- In a medium saucepan, combine the mashed bananas, 1 tablespoon butter, and ¼ cup granulated sugar. Heat over medium, stirring frequently, for about ten minutes, until some of the moisture has evaporated. Remove from the heat and let cool to room temperature. Put the mixture in a food processor or blender and mix until smooth. Add the yellow food coloring (you will need quite a bit to make it yellow – about ½ teaspoon) and mix again. The puree will be a very bright yellow but will mellow out when added to butter mixture (you can refrigerate the puree for up to 24 hours, but you will want to add the puree to the buttercream at room temperature).
- In the bowl of a stand mixer fitted with the paddle attachment, beat the butter until smooth. Scrape down the sides, add the vanilla, rum, and salt, and mix again until combined. Add the cooled banana puree, and mix until combined. Add the powdered sugar and mix on low until combined, then increase the speed to medium and beat until smooth and creamy, scraping the sides as needed. Switch to the whisk attachment. Add ¼ cup of heavy cream, and mix on low until combined, then increase the speed to medium and beat until fluffy and light (if the buttercream isn’t turning fluffy and light, add another ¼ cup heavy cream and beat again).
Note: The banana puree can get a little bit ‘rubbery’ especially if it’s been chilled, and needs a little help lightening up in the buttercream. Heavy cream and the whisk attachment should do this, but if it still is having trouble, add another stick of butter to the buttercream at the end, one tablespoon at a time, until it smooths out. I promise it’s worth it.