Preheat your oven to 350°F (175°C) and grease a donut pan.
In a mixing bowl, combine the mashed bananas, honey, milk, egg, vanilla extract, and melted coconut oil.
In a separate bowl, whisk together the oats, flour, baking powder, and cinnamon.
Gradually add the dry ingredients to the wet ingredients, stirring until just combined.
Spoon the batter into the greased donut pan, filling each cavity about 3/4 full.
Bake for 12-15 minutes or until the donuts are lightly golden and a toothpick inserted in the center comes out clean.
Allow the donuts to cool in the pan for 5 minutes before transferring to a wire rack.
Enjoy as is or top with a light glaze or a sprinkle of cinnamon sugar.