Preheat oven to 350 degrees F. Spray a 9x13-inch inch baking pan with cooking spray. Set aside.
In a large bowl, mix together the cake mix, Greek yogurt, and water. Mix well until combined. Pour mixture into prepared baking pan, spreading batter out evenly.
Bake 25 to 30 minutes or until toothpick inserted in center comes out mostly clean. Cool completely before frosting.
In a medium bowl, whisk together pudding mix, milk, and vanilla extract until thickened and no lumps remain. Fold in whipped topping. Spread frosting over cooled cake and top with lots of sprinkles. Enjoy!