In a blender, blend banana, macadamia nut milk, matcha powder, vanilla and sugar on high until completely smooth.
In a large bowl, whisk oat flour, almond meal, gluten-free flour and baking powder together then pour the wet mixture into the bowl and stir to combine well.
Grease the muffin pan, use a non-stick pan, or use muffin liners. Add the batter into the muffin pan filling each about 3/4 way to the top. Yields about 9 muffins.
Bake for about 22 minutes. Allow to cool for 30 minutes before removing from the pan.