This Keto Version captures everything you love about classic banana bread ,the warm baking aromas, the light fluffy texture, and that sweet banana flavor minus the carbs.
Preheat oven to 350°F. Grease a standard loaf pan with 2 tsp butter, then dust with 2 tsp coconut flour. Tap out excess.
Melt the remaining butter in the microwave and set aside to cool slightly.
In a large bowl, whisk together the remaining coconut flour, almond flour, ground flax-seed, baking powder, xanthan gum, cinnamon, nutmeg, and salt. Set aside.
In the bowl of a stand mixer (or large mixing bowl with hand mixer), beat the eggs and sweetener on medium speed until light, fluffy, and pale in color (about 3–4 minutes).
Add the banana extract, vanilla extract, apple cider vinegar, and melted butter. Mix until combined.
Add the dry ingredients in two additions, alternating with the sour cream. Mix just until a thick batter forms — do not over-mix.
Fold in half of the chopped walnuts.
Pour the batter into the prepared loaf pan and sprinkle the remaining walnuts on top.
Bake for 30 minutes. Tent the top loosely with foil to prevent over-browning, then bake another 25–30 minutes, until a toothpick inserted in the center comes out clean.
Remove from oven and cool in the pan on a wire rack for 15 minutes. Carefully remove the loaf from the pan and let it cool completely before slicing.