01 - Preheat the oven to 350°F. Line two baking sheets with parchment paper.
02 - In a medium bowl, whisk together the gluten-free flour, baking soda, and fine sea salt. Set aside.
03 - In a large mixing bowl, beat the softened butter, brown sugar, and granulated sugar using an electric mixer until light and creamy, approximately 2 minutes.
04 - Add the egg and vanilla extract to the creamed mixture, mixing until fully combined and smooth.
05 - Gradually add the dry ingredient mixture to the wet ingredients, mixing just until incorporated. Avoid overmixing.
06 - Gently fold in the dark chocolate chips and chopped peanuts until evenly distributed throughout the dough.
07 - Scoop tablespoon-sized portions of dough onto the prepared baking sheets, spacing them about 2 inches apart.
08 - Bake for 10–12 minutes, or until the edges are golden and the centers are just set.
09 - Allow cookies to rest on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.