1. Preheat oven to 375°F (190°C) and line baking sheets with parchment paper.

2. In a medium bowl, whisk together flour, baking soda, and salt. Set aside.

3. In a large bowl, beat softened butter and granulated sugar until light and fluffy, about 2–3 minutes.

4. Add egg and vanilla extract and mix until combined.

5. Gradually mix in the strawberry gelatin until fully incorporated. Add food coloring if using.

6. Slowly add dry ingredients to wet ingredients, mixing on low speed until just combined.

7. Add milk one tablespoon at a time if dough feels too stiff.

8. Optional: Chill dough for 30 minutes to reduce spreading.

9. Roll dough into 1-inch balls and roll each ball in sugar or sprinkles.

10. Place dough balls 2 inches apart on prepared baking sheets.

11. Bake for 8–10 minutes, until edges are set and cookies look slightly puffy.

12. Immediately press a chocolate kiss into the center of each hot cookie.

13. Allow cookies to cool on baking sheet for 5 minutes, then transfer to a wire rack to cool completely.