Preheat oven to 350 degrees F. Lightly spray a 9X5-inch loaf pan with non-stick spray and set aside. In a stand mixer, mix the brown sugar, molasses, buttermilk, vanilla and eggs.
Sift together the flours, baking soda, baking powder, cinnamon, nutmeg, ginger and cloves. Stir in the amaranth and salt. Add the flour-amaranth and melted coconut oil to the stand mixer and mix on medium speed, until just combined. Use a rubber spatula to scrape down the sides, if needed. Mix until just combined. Stir in carrot and pecans.
Pour the batter into the prepared loaf pan and spread the top out evenly. Bake in the preheated oven for 45-50 minutes, until a toothpick inserted in the center comes out clean. Cool in pan about 15 minutes, then cool completely on a wire rack before slicing.