Preheat the oven to 350 F and line your cookie sheet with parchment paper.
In a large mixing bowl, cream softened butter and sugar together.
Add vanilla and egg.
Use a hand mixer and mix until well combined.
Add the dry ingredients; flour, dry pudding mix, baking soda and salt to the wet ingredients. Mix until a soft dough forms.
Divide the dough into two equal parts and place in two bowls.
Add red jello powder to one bowl and green jello powder to the other.
Add half of the sprinkles to each bowl and mix well.
Use a cookie scoop to drop cookie dough balls onto the prepared baking sheet.
Bake cookies for 8-10 minutes in the preheated oven, until the edges just start to turn golden brown.
Place the cookies on a wire rack to cool before storing them in an airtight container.