01 - Preheat your oven to 350°F. Line two baking sheets with parchment paper.
02 - In a medium bowl, whisk together the flour, baking soda, baking powder, and salt. Set aside.
03 - In a large bowl, cream the softened butter and granulated sugar together until light and fluffy, about 2 minutes.
04 - Add the egg and vanilla extract, beating until well combined.
05 - Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
06 - Divide the dough evenly into two bowls. Add one flavor of Jello powder to each bowl (about 3 tablespoons per bowl) and knead until the color and flavor are well incorporated.
07 - Scoop a tablespoon of dough, roll into a ball, then gently roll in extra granulated sugar. Repeat for all dough.
08 - Place cookies 2 inches apart on the prepared baking sheets.
09 - Bake for 8 to 10 minutes, or until the edges are set but the centers look slightly underbaked for extra chewiness.
10 - Allow cookies to cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.