In a large bowl add the softened butter and sugar and whip together with a hand mixer, or whisk. Once combined and smooth you can stop- about 30 seconds. Scrape the sides of the bowl down if needed, then mix again.
Add in the beaten eggs, bananas and coconut milk and keep mixing until combined well.
Slowly add in the coconut flour, oat flour, baking soda, salt and vanilla. Keep mixing until batter has formed and is mixed through.
Fold in walnuts and chocolate chips and then pour into your pre greased loaf pan. Give it a little shake to make sure the batter has evenly spread out.
*optional: peel and slice banana in half long ways and then gently press both 2 slices into the top of the batter, running along the top.*
Pop in the oven on the middle rack for 50 minutes until the edges start to crisp up. If the top begins to brown or darken too quickly, lightly cover with foil and keep cooking. Stick a toothpick or knife into the center, if it comes out clean you’re good to pull it out of the oven. It not, leave in for another 3-5 minutes.
Remove from pan and place on a cooling rack to cool before slicing.