Pre-heat your oven to 325*F.
Add the almond flour, lupin flour, baking powder, baking soda, cinnamon, xanthan gum and salt to a bowl. Whisk to combine, then set aside.
In another larger bowl, add the melted butter, mashed banana and monkfruit sweetener. Whisk well to combine.
Add the eggs and vanilla extract to the same bowl and whisk again, very well, until bubbles can be seen at the top of the mixture.
Next, add the dry ingredients from before to the banana mixture.
Stir to combine. You want to stir until everything becomes quite thick.
Stir in chocolate chips, walnuts and or pecans at this point if you'd like!
Grease a standard 8x4 inch loaf pan with butter or oil then use a spatula to scrape the batter into the pan. Even out the top. Sprinkle with a little extra granulated sweetener and cinnamon (option, I like to use a little truvia and cinnamon).
Bake the loaf for roughly 55-65min or until a toothpick comes out clean. Cover the pan lightly with tinfoil prior to baking and remove halfway to three quarters of the way through if you'd like to prevent the crust from browning too quickly.
Let the loaf cool completely in the pan before turning out onto a plate. Slice and serve! Enjoy your Low Carb Keto Banana Bread!