Preheat oven to 350° F / 176° C. Grease 8x4 loaf pan (standard size) or line with parchment paper.
Combine all wet ingredients (pumpkin puree, coconut milk, coconut oil, maple syrup, eggs, and vanilla) in a bowl. Whisk well to combine.
Stir dry ingredients (almond flour, coconut flour, flax meal, cacao powder, cinnamon, baking soda, and salt) together in a second bowl. Add in optional pecans.
Gently combine the dry bowl into the wet bowl to form batter. Stir just enough to evenly incorporate; do not over mix. Fold in chopped cacao paste. Save a few larger pieces to sprinkle on top of the loaf as decoration, if desired.
Pour batter into loaf pan. Arrange cacao paste on top as needed. Bake for 50 minutes, until a toothpick inserted into the center comes out clean. Remove from heat, cool, and slice into 8 portions.