1. In a large bowl, beat softened butter, granulated sugar, and brown sugar until light and fluffy.

2. Add eggs one at a time, mixing well. Stir in vanilla extract.

3. In a separate bowl, whisk together gluten-free flour, cream of tartar, baking soda, and salt.

4. Gradually add dry ingredients to the wet mixture, mixing until a soft dough forms.

5. Cover dough and refrigerate for 30–60 minutes.

6. Preheat oven to 350°F (175°C) and line baking sheets with parchment paper.

7. Mix ¼ cup sugar and cinnamon in a small bowl. Roll chilled dough into 1.5-inch balls and coat in cinnamon sugar.

8. Place on prepared baking sheets, spacing about 2 inches apart.

9. Press a red and green gumdrop on each dough ball.

10. Bake for 9–11 minutes, until edges are set and centers look slightly underbaked.

11. Let cookies cool on the baking sheet for 5 minutes before transferring to a wire rack.