Preheat oven to 350°F degrees. In a large bowl, cream together butter and sugar with a mixer until light and fluffy. Blend in egg and vanilla.
In a separate bowl, whisk together flour, baking powder, baking soda and cream of tarter. Gradually add flour mixture to the wet ingredients.
Divide the dough into four sections. Sprinkle two tablespoons of jello mix into each section and then knead the dough until combined. You can add a few drops of food coloring in, if you’d like the color to be more vibrant.
Roll dough into 1-inch balls. If desired, you may roll the balls into the extra jello powder or sugar for a sweeter cookie. Then place dough onto the baking sheet about two inches apart. Flatten the dough with the bottom of a cup or bowl to allow the cookies to cook evenly.
Bake for 8-10 minutes. Remove cookies from the pan and allow to cool on a wire rack.