Ingredients
Method
- Preheat the oven to 350°F (177°C). Line a 12-cup muffin pan and a second pan with 6 liners to accommodate approximately 18 cupcakes, then set aside.
- Whisk the flour, baking soda, baking powder, cinnamon, and salt together and set the mixture aside.
- Beat the butter, brown sugar, and granulated sugar on medium-high speed for about 3 minutes until creamed, scraping the bowl as needed. Add the eggs, sour cream or yogurt, and vanilla extract, then beat on medium-high until combined. Mix in the mashed banana.
- Incorporate the dry ingredients with the mixer on low speed. Slowly pour in the buttermilk while continuing to mix on low until just combined, being careful not to overmix. Whisk by hand if necessary to incorporate any dry pockets at the bottom of the bowl.
- Fill the liners two-thirds full with batter. Bake for 18 to 20 minutes, or until a toothpick inserted in the center comes out clean. For mini cupcakes, bake for 11 to 13 minutes at the same temperature.
- Cool the cupcakes in the pan on a wire rack for 20 minutes, then transfer them directly to the rack to cool completely before frosting.
- Beat the cream cheese and butter on high speed until smooth. Add 3 cups of confectioners’ sugar, vanilla, cinnamon, and salt. Mix on low for 30 seconds, then increase to high and beat for 2 minutes, adding more sugar if a thicker consistency is preferred.
- Refrigerate the frosting for at least 20 minutes if desired to help it hold its shape. Frost the cooled cupcakes using a piping tip or spatula, then garnish with banana slices and crushed Nilla Wafer cookies.
- Cover leftover cupcakes tightly and store them in the refrigerator for up to 3 days, using a cupcake carrier for transport if needed.
Notes
Banana Ripeness: I always wait until my bananas are covered in dark brown spots because that extra natural sugar makes the cupcakes so much more flavorful.
Texture Secret: One thing I learned the hard way is to stop mixing as soon as the buttermilk is incorporated to keep the crumb light and fluffy.
Make Ahead Strategy: These actually taste even better the next day after the flavors have had time to meld, so I often bake the bases a day early and frost them just before serving.
Frosting Quality: I have found that using the brick-style cream cheese is essential here, as the spreadable kind in the tub is too thin and will make your frosting runny.
Dairy Swap: I prefer using full-fat Greek yogurt when I do not have sour cream on hand because it provides that same tangy moisture that balances the sweetness.
Serving Suggestion: Since fresh banana slices brown quickly, I only add them at the very last second or stick with crushed Nilla Wafers for a crunch that stays fresh.
Storage Tip: I always keep these in the refrigerator because of the cream cheese frosting, but I recommend letting them sit on the counter for twenty minutes before eating so the cake reaches the perfect texture.