In a medium to large mixing bowl, cream together the softened butter and sugar. Then stir in the egg and vanilla extract until just combined.
In another bowl, stir together the flour, baking soda and baking powder. Then combine the wet and dry ingredients into the larger bowl and stir until a soft dough ball forms.
If you are using multiple Jell-O flavors, divide the dough. For example, I used three flavors in the batch you see pictured here, so I divided the dough into three equal parts. Mix the Jell-O powder into the dough until well combined.
Form balls with the dough; this recipe will make 12-13 cookies in total. Place a baking sheet lined with parchment paper or a baking mat.
Bake at 350°F for 10-12 minutes. Allow cookies to cool on a cooling rack before eating.
Notes
Since I divided the dough into three parts, I used 1/4 cup Jell-O powder in each part (3/4 cup total) to color and flavor this batch. If you mix the Jell-O powder into the dough by hand, it can temporarily stain your hands, even after washing. This will fade quickly after a couple of washes, so don’t worry if you notice this on yourself or kids.