Preheat the Oven: Preheat the oven to 350°F and line the muffin tin with paper liners or silicone molds.
Prepare the Dry Ingredients: In a large bowl, mix the almond flour, coconut flour, baking powder, baking soda, salt, cinnamon, and sweetener.
Mix Wet Ingredients: . In the second bowl, whisk eggs, almond milk, melted butter, and vanilla extract.
Combine and Fold in Zucchini: Add the wet mixture to the dry ingredients, stirring until just combined. Fold in the grated zucchini and optional nuts or chocolate chips.
Bake: Bake for 18–22 minutes or until a toothpick inserted in the muffins comes out clean.
Cool and Serve: Let them cool in the tin for 5 minutes before transferring to a wire rack. Store them in a refrigerator or serve them warm.