Preheat the oven to 350 F. In a large bowl, mix together cake mix, eggs, and vegetable oil until smooth. Place the sanding sugar into a shallow dish.
Use a cookie scoop to form the cookie dough into balls, and roll each one into the sanding sugar. Place the cookies onto a large ungreased baking sheet at least 2-inches apart. Place one heart sprinkle on each cookie. Bake for 10-12 minutes.