Preheat oven to 350°F Grease a 12-cup muffin tin or line it with paper muffin cups.
Mix together pumpkin puree, egg, sugars, molasses, vanilla and oil. Stir in flours one at a time, adding the xanthan gum, salt, baking powder, baking soda, and pumpkin pie spice with the millet flour. Stir in any optional ingredients now.
Pour batter into muffin cups, filling them most of the way full. Sprinkle pumpkin seeds on top of each.
Bake 20-25 minutes, or until muffins test done. Remove from oven and allow to cool in pan only a few minutes; remove to a wire rack to finish cooling.