Preheat oven to 350 degrees. Line your baking sheets with parchment paper or silicone baking mats.

In a stand mixer or mixing bowl, mix together the melted butter and sugar on medium-low speed. Add the egg and mix until combined. Add the salt, baking powder, baking soda and xanthan gum and mix until combined.

Add the flour and mix until incorporated. Add the white chocolate chips and sprinkles and mix just until they are evenly distributed throughout.

Scoop the cookies using a 1 1/2 Tbsp cookie scoop and place the dough 2-3 inches apart on the prepared baking sheet. Bake for 10 minutes or until the cookies lose their doughy shine and have spread slightly.

If desired, flatten the cookies slightly by pressing down on them slightly with a spatula. This will give them a nice crinkle on the top and keep them from looking too puffy. (Entirely optional, it won't affect the taste.) If desired, press additional white chocolate chips into the tops of the cookies before baking.