Preheat the oven to 400 F degrees.
Line a 12-cavity muffin pan with parchment paper liners, or spray with nonstick baking spray. Set aside.
In a large mixing bowl, mix together with a spatula the egg, mashed bananas, vanilla, coconut oil, and yogurt. Add in the oat flour, cocoa powder, sugar, baking powder, baking soda, and salt. Toss in the chocolate chips. Mix until just combined.
Spoon the batter (or use a Baking Scoop Disher like we did…it makes this process so easy!) evenly across the 12-cavity muffin pan. Fill to the top (they batter won’t rise that much while baking). We topped with a few extra chocolate chips, but totally optional. You could even top with slices of bananas!
Bake for 20-25 minutes, or until a toothpick inserted into the center comes out clean with a few moist crumbs. Let muffins cool for 10 minutes, then transfer to a cooling rack.
We highly suggest you enjoy while still slightly warm