Preheat the Oven: Preheat your oven to 350°F (175°C).
Prepare the Dry Ingredients: In a medium bowl, mix together 1 cup gluten-free flour, 1 teaspoon baking soda, and a pinch of salt. Set aside.
Prepare the Wet Ingredients: In a separate bowl, combine 1 cup peanut butter, 1/2 cup sugar (or sugar substitute), and 1 large egg. Stir until smooth and well combined.
Mix Wet and Dry Ingredients: Gradually add the dry ingredients to the wet ingredients. Stir until fully combined into a thick dough.
Shape the Dough: Scoop out spoonfuls of dough and roll them into balls, about 1 inch in diameter. Place them on a baking sheet lined with parchment paper, spacing them about 2 inches apart.
Flatten the Dough: Use a fork to press down on each dough ball, making a criss-cross pattern.
Bake: Bake the cookies for 8-10 minutes, or until the edges are golden brown. The centers should look soft but will firm up as they cool.
Cool and Enjoy: Let the cookies cool on the baking sheet for a few minutes, then transfer them to a wire rack to cool completely.