Banana Spiced Cupcakes with Peanut Butter Caramel Buttercream

I made two banana cupcake recipes and this one came out the winner, because it was slightly more moist and I love the tiny hint of cinnamon. There's always a chance that cupcakes baked with fruit can turn out very muffin-like, but I'm pleased that both recipes came out with a great cake crumb. I topped both recipes with the same amazing buttercream, which was everyone's favorite part.

Banana Spiced cupcakes on left. Even with a bit of spice, the banana flavor still shines through.

Banana Spice Cupcakes with Peanut Butter Caramel Buttercream 
Recipe adapted from: Lil Luna
Yield: 20 cupcakes

Ingredients
20 cupcake liners
4 large eggs
1/2 cup butter, softened
1 cup pureed bananas (process 2 large bananas in a blender)
1/2 teaspoon banana extract
1 1/2 cups cake flour
3/4 cup sugar
2 teaspoons baking powder
1/2 teaspoon baking soda
1/4 teaspoon salt
1 teaspoon cinnamon

Directions
Preheat the oven to 350. Prepare two muffin tins by lining with paper liners.

Separate the eggs and beat the egg whites until stiff peaks form, then set aside.

In a large bowl or the bowl of a stand mixer, beat the butter until light and fluffy. Add the pureed bananas, egg yolks, and vanilla, and mix until smooth. Gently fold in 1/3 of the egg white mixture.
In a medium bowl, whisk together the flour, sugar, baking powder, baking soda, salt, and cinnamon. Gently fold the dry ingredients into the wet ingredients until just combined. Gently fold in remaining egg whites.

Fill paper baking cups half full and bake 13-15 minutes, or until a toothpick inserted in the center comes out clean. Remove and let cool completely.

Peanut Butter Caramel Buttercream
16 tbsp (2 sticks) unsalted butter, at room temperature
2/3 cup smooth peanut butter (not natural)
3 cups powdered sugar
pinch of table salt
1 tsp vanilla extract
4 tbsp caramel sauce

Directions
In a stand mixer fitted with the paddle attachment, beat butter and peanut butter at medium-high speed until smooth.  Add the powdered sugar and salt to the bowl and beat at low speed just until the combined. Scrape down the sides of the bowl and beat the mixture on med-high until fully combined. Mix in vanilla and caramel sauce and beat until combined.  Scrape down the sides of the bowl again then beat until the frosting is light and fluffy. Pipe onto cooled cupcakes.