Preheat oven to 350.
In a large mixing bowl, mash ripe bananas. Try to get out as many chunks as possible. Add in eggs and mix until they are whisked. Finally, add in the rest of the wet ingredients (vanilla, oil, maple syrup, nut butter) and mix until well combined.
Add in flour and baking soda. Mix very well. Fold in chocolate chips and mix again.
Grease a donut pan with coconut oil spray / non stick spray. Pour in batter to fill 3/4 the way up each vessel. batter should make 10-12 donuts.
Bake for 15 - 20 minutes.
While the donuts are baking, make the frosting. Melt chocolate chips with coconut oil in the microwave on medium hi for 90 seconds. Mix very well to continue to melt. Depending on the size of your chips, you may need to melt for longer.
Once the donuts are ready, let cool and remove from pan. Place on a drying rack with paper towel underneath. Use a spoon to spread melted chocolate on top of each donut. Optional to sprinkle chocolate sprinkles on top. Enjoy right away or let the chocolate cool/harden before eating.
Store in the fridge for up to 3/4 days.