Preheat the oven to 180C/356F.
Heat the butter over a low-medium heat for about 5 minutes or until it begins to brown. You'll know when it has browned because it will smell nutty, potentially be bubbling, and have golden flecks in the liquid. Once it has browned, add the mashed banana, and continue to cook for a few more minutes on a low heat. Once the bananas are cooked and fragrant, set aside to cool for about 5-10 minutes.
In a large bowl, add the butter banana mixture along with the maple syrup, eggs, vanilla bean paste and salt. Mix well to combine.
In a small bowl, mix the plant milk of choice and apple cider vinegar together to form buttermilk. This will help give the loaf some oomph.
Mix together the flours, baking soda and powder, spices and coconut sugar. Add this to the banana mixture, and stir thoroughly to combine.
Add the ‘buttermilk’ to the batter, and stir well until fully combined. Finally, add the chocolate chips (and blueberries, if you're using them) and stir through.
Pour the loaf into a greased silicon loaf pan. Apparently you don’t need to grease silicon, but I don’t trust gluten free baked goods, sorry bout it.
Cook the loaf for 30-40 minutes, or until the top is golden. Once it is, cover with foil, and continue to cook for an additional 30-40 minutes, until a skewer comes out clean. The loaf is a chonk, so it will take an hour to an hour and twenty to cook. Worth the wait, tbh.
Once cooked, remove from the oven and allow to cool slightly before transferring to a cooling rack. Gently slice and serve with a little butter or a drizzle of maple.
Store in an airtight container and eat within 2-3 days. You could probably slice it and freeze it, too.