Preheat oven to 350 F.
In a medium-sized bowl, whisk together flour, baking powder, baking soda, and salt.
In another medium-sized bowl or the bowl of a stand mixer, cream butter, sugar, and brown sugar until the mixture looks like wet sand (about two minutes on high speed).
Add mashed bananas to the butter mixture and mix until combined.
Mix in eggs one at a time to the butter mixture, mixing until fully incorporated.
Mix in coconut milk until just combined.
Add dry ingredients to wet ingredients a little bit at a time, mixing until just combined.
Fold in oats and chocolate chips.
Fill greased muffin tins 3/4 full.
Bake for 20 minutes or until a toothpick comes out dry.
Remove muffins from the tins as soon as they are cool enough to touch. Once cooled completely, store in an airtight container for up to five days.