Preheat the oven to 350 degrees. Spray the wells of your mini muffin tin with non-stick cooking spray and set aside.
Next, mash the bananas together in a mixing bowl; you want them as pureed as possible (no worries if there are still a few lumps!).
Add in yogurt, honey, egg, and vanilla. Mix to combine. Then, add in flour, cocoa, and baking soda.
Mix until the batter is smooth, scraping down the sides of the bowl as you go/as needed.
Scoop batter into prepared muffin tin wells, filling each well approx. 3/4 of the way full. Repeat until all wells are filled (you will have extra batter for another round).
Top each well of batter with a few mini chocolate chips.
Bake at 350 degrees for 10-13 minutes. Once done, remove from oven, allow to slightly cool and enjoy.