Preheat oven to 180°C. Lightly grease a 12-cup muffin pan or use foil liners; set aside.
In a blender container, grind gluten-free quick oats until the consistency of oat bran. Measure 90g and set aside.
In a large bowl, beat together the egg, brown sugar, and oil. Stir in the oat bran and vanilla.
In a separate bowl, mix together the yogurt and baking soda; set aside.
Sift together the gluten free all purpose flour, baking powder, salt, and xanthan gum. Add to the egg-sugar mixture alternately with the yogurt mixture.
Fill the muffin cups and bake for 20-25 minutes, until the muffins are lightly browned. Remove from the pan and cool on a wire rack. Makes 12 muffins.