Preheat the oven to 200°C (392°F)
Whisk and combine the white rice flour, tapioca flour, corn starch, brown rice flour, xanthan gum, baking powder, baking soda, salt, ground cinnamon, and nutmeg. Set the mixture aside.
Whisk and combine the eggs, vegetable oil, and granulated sugar. Then add the sour cream, vanilla extract, milk, and whisk until combined. Pour the wet ingredients into the flour mixture and mix using a spatula. Now, add the chocolate chips and fold them into the gluten free muffin batter.
Align a muffin tin with muffin liners or grease the bottom and sides of your muffin pan. Fill each muffin cup all the way to the top.
Bake the muffin at 200°C (392°F) for 5 minutes, then reduce the temperature to 180°C (356°F) and bake the muffins for another 15-18 minutes or until a toothpick inserted in the center of the muffins comes out clean.
Allow the muffins to slightly cool in the tin for 5 minutes before transferring them to a cooling rack.