Prior to starting, preheat oven to 350ºF. Line a standard size loaf pan with parchment paper. I find that lightly greasing the pan with coconut oil helps the parchment stick to the sides of the pan better.
In a large mixing bowl, combine the almond flour, coconut flour, collagen, sweetener, flax meal, baking powder, baking soda, salt, and pumpkin spices. Mix together well.
In another large mixing bowl, whisk the eggs, then add the pumpkin puree, coconut oil, and vanilla extract. Whisk until combined well. Using room temperature eggs and slightly heating the coconut oil will help keep the batter thin to make a beautiful bread.
Add the dry ingredients into the wet ingredients, and stir until combined. The coconut flour will absorb liquid and the batter will continue to thicken as it sits. It’s easier to get in the pan if you work quickly before it gets too thick.
Fold in the walnuts, seeds, or chocolate chips, if using.
Add the pumpkin bread batter to the prepared loaf pan. If desired, garnish the top of the loaf with additional nuts, seeds, or chocolate chips.
Cover the loaf pan with foil, and bake the bread for 1 hour. Remove the foil, and continue baking the bread for 10-15 minutes, until the top of the loaf is lightly golden and the center is fully set. Allow the bread to fully cool prior to slicing.