Preheat the oven 350° F. Line a 9x5 loaf pan with parchment paper and lightly spray, then set aside.
In a large mixing bowl, combine brown rice flour, almond flour, sugar, baking powder, cinnamon, nutmeg, and salt.
In a smaller bowl mix almond milk, ground flaxseeds, oil, and vanilla.
Stir wet ingredients into dry ingredients and mix until batter is smooth. Fold the shredded zucchini into the batter.
Scoop the batter into the prepared baking pan and bake for 70-90 minutes, or until a toothpick inserted into the center comes out clean.
Cool in pan for about 10 minutes, then remove from pan and allow to cool completely on a wire rack.