Preheat your oven to 350°F (175°C) and grease a 12-cup muffin tin or line it with paper liners.
In a medium bowl, whisk together the gluten-free flour, baking powder, baking soda, cinnamon, nutmeg, ginger, cloves, and salt.
In a separate large bowl, mix the pumpkin purée, eggs (or flax eggs), melted butter (or coconut oil), brown sugar, and vanilla extract until well combined.
Slowly add the dry ingredients to the wet mixture, stirring until just combined. Be careful not to overmix. Fold in any optional mix-ins like chocolate chips or nuts.
Divide the batter evenly into the muffin cups, filling each about ¾ full.
Bake for 20-25 minutes or until a toothpick inserted into the center comes out clean.
Allow the muffins to cool in the tin for 5-10 minutes before transferring them to a wire rack to cool completely.