Preheat the oven: Heat it to 350°F (175°C). Line or grease a muffin tin.
Mix dry ingredients: Whisk flour, baking powder, baking soda, salt, and xanthan gum.
Prepare wet mixture: In a separate bowl, whisk melted butter, sugar, eggs, milk, and vanilla extract.
Combine: Gradually fold dry ingredients into wet, stirring until just combined.
Add chocolate chips: Gently mix them in, saving a few for topping.
Fill muffin cups: Pour batter evenly into liners, filling each about ¾ full.
Bake: Place in the oven for 20 minutes or until a toothpick comes out with a few crumbs.
Cool slightly & enjoy: Let them sit for 5 minutes, then dig in.