Instructions

1. Place a rack in the center of the oven and preheat to 375 degrees F.  Line 6 muffins tins with parchment liners and set aside.
2. Melt butter in a saucepan over medium heat.  Butter will begin to foam and crackle as it melts.  When the crackling subsides, the butter will begin to brown.  Swirl the pan as the butter cooks.  When the butter browns and begins to smell nutty, remove the pan from the flame and transfer the butter to a small bowl.  Taking the butter out of the hot saucepan will stop the butter from overcooking and burning.  Set aside to cool.
3. In a large bowl, whisk together flour, sugar, baking soda, salt, and cinnamon.
4. In a medium bowl, whisk together eggs, vanilla extract, and buttermilk.  Whisk in the mashed bananas.  When butter has cooled, whisk in the browned butter.
5. Add the wet ingredients, all at once to the dry ingredients.  Fold together, making sure to scrape the bottom of the bowl to reveal any hidden pockets of flour.  Fold together ingredients, but try not to over stir.
6. Spoon batter into prepared pan.   Bake for 23-28 minutes, or until a skewer inserted into one of the muffins comes out clean.  Remove from the oven and allow to rest in the pan for 15 minutes, before inverting onto a wire rack to cool completely before frosting.
7. While your cake is cooling, prepare the frosting. In a stand mixer fitted with the paddle attachment, beat your butter just to get it out of its stick shape. Add oats, cinnamon, butter extract, baking soda, and salt, and beat until combined. Slowly add powdered sugar, increasing the speed of the mixer until it is on high. Keep beating it on high until the frosting gets nice and fluffy. Pause and scrape down the sides of the bowl as needed. Sample the frosting – add more sugar or salt as needed to balance the flavors.
8. Once your cupcakes are cool, frost as desired. Enjoy!