Preheat the oven to 350 degrees.
Thoroughly grease a mini muffin pan and set aside.
Using a hand mixer or a stand mixer fitted with the paddle attachment, cream the butter and sugar for 1-2 minutes or until fluffy. Scrape down the bowl once complete.
Add in room temperature eggs and beat until combined.
Add mashed bananas and vanilla extract. Mix until combined. Scrape down the bowl once complete.
In a separate bowl, whisk together dry ingredients (flour, baking soda, salt).
Add dry ingredients to wet ingredients in 2-3 portions, mix until combined.
Place the batter into a gallon bag and cut a 1 cm tip in the corner of the bag. Use it as a piping bag to add batter to each mini muffin cavity. You may also just spoon the batter individually. Fill each cavity about ¾ full.
Bake for 12-15 minutes or until a toothpick comes out clean.
While the muffins bake, make the topping. Mix cinnamon and sugar in a medium-sized bowl and set aside.
Immediately turn the muffins out from the pan after removing them from the oven and toss them in cinnamon and sugar. Enjoy warm or at room temperature!