Combine butter with sugar and beat on medium speed until well creamed together.
Add eggs and vanilla extract. Mix into butter and sugar until egg is well beaten.
In a separate bowl, combine flour, baking soda and cream of tartar. Slowly add the dry ingredients into batter and beat on medium low speed until well combined and dough forms. Add ½ cup of sprinkles to the dough and mix until the sprinkles incorporate.
Refrigerate dough for a minimum of 30 minutes and up to 1 hour.
Preheat oven to 350° F.
Use a large cookie scoop (3 tbsp) and scoop cookie dough into a bowl of sprinkle. Roll the top of the dough in the remaining sprinkles and then place on a baking sheet lined with parchment paper.
Bake at 350° F 10-12 minutes. Allow cookie to cool on the baking sheet for several minutes and then transfer to a wire rack to cool completely.