1. Preheat the oven to 375 degrees F. Line a baking sheet with a piece of parchment paper.
2. In a medium mixing bowl, stir together the rice flour, potato starch, tapioca flour, xanthan gum, baking powder, baking soda and salt. Set aside.
3. In a large mixing bowl using an electric hand mixer or a stand mixer fitted with the beater blade, beat the butter, brown sugar and granulated sugar until light and creamy. One at a time, add the eggs and beat until well combined. Add the vanilla and then gradually add in the flour mixture. Beat just until combined. Stir in 1 1/2 cups chocolate chips.
4. Form balls of dough, about 50 grams or a little less than 3 tablespoons in size, and roll the tops and sides of the balls in the remaining 1/2 cup chocolate chips. Place the balls 2 1/2" apart on the prepared baking sheet.
5. Bake for 9-12 minutes or until lightly browned and the surface no longer appears wet.
6. Let cool for 5 minutes and then remove to a wire rack to cool completely. Store in an airtight container for up to 4 days.