3/4cupgluten-free oat flourI used Bob's Red Mill; you can also use a food processor to grind your own
Preheat oven to 350 degrees.
Place milk and vinegar in a cup or bowl; let stand for 5-10 minutes until lightly curdled. Add oats and let sit for 15-20 minutes until softened.
Meanwhile, mix together sugar, egg, banana, olive oil, vanilla, and cinnamon. Add oat mixture and mix well. Mix together oat flour, cocoa, baking powder, baking soda, and salt. Add to batter and mix until just blended. Stir in chocolate chips.
Fill paper lined muffin tins.
Bake 15-17 minutes, until toothpick comes out clean when inserted in center of muffin.