Preheat oven to 350ºF. Line a baking sheet with parchment paper. Set aside.
In a large bowl, add cream cheese and butter. Beat with an electric hand or stand mixer until smooth and fluffy. Scrape down sides of bowl.
Add egg and vanilla extract. Beat until smooth. Scrape down sides of bowl.
Add Yellow Cake Mix. Beat on low until incorporated. Fold in the sprinkles.
Roll the cookies into small balls, using about 1 1/2 tablespoons of dough for each. Roll each dough ball into the powdered sugar to coat. Place on prepared baking sheet about 3 inches apart.
Bake until the top of the cookies no longer look wet and hold their shape, about 10-13 minutes. Enjoy!