Coat a 9-by-9-inch loaf pan with cooking spray. In a large bowl, combine the tapioca flour, cornmeal, brown rice flour, cornstarch, sugar, baking powder, baking soda, and sea salt. Whisk well to combine. In a separate bowl, combine the butter, almond milk, agave nectar, and egg substitute and whisk well to combine.
Add the wet ingredients to the dry ingredients and mix well. Add the raw cacao nibs, chili powder, and cinnamon. Transfer the mixture into the loaf pan. Bake until golden brown, about 35-40 minutes. Remove from the oven and serve.