Preheat the oven to 350 degrees. Spray a 9 by 12 inch baking dish with cooking spray.
Whisk together the eggs, oil, water, and vanilla, Add the cake mix and whisk until fully combined. Pour the batter into the prepared pan and bake for 25 minutes or until a toothpick inserted into the center comes out clean. Let the cake cool completely in the pan set on a wire cooling rack.
When the cake is cooled, crumble into a large mixing bowl. Add the frosting a little at a time and mix well using your hands until the cake crumbs just hold together. You don’t want to add too much frosting as the pops will be heavy and greasy.
Line a baking dish with parchment paper and freeze the balls for 1 hour. Then transfer to the refrigerator. (You can also just refrigerate for 2 hours or more.)
Melt the chocolate and vegetable oil together and pour into a large liquid measuring cup or glass.
Put the sprinkles into a small bowl.
Working with just a few of the balls at a time, dip the lollipop stick into the chocolate about ½ inch. Push into cold cake pop then dip the cake pops in chocolate, letting the excess drip off. Coat with sprinkles. Stick into a Styrofoam block to keep the pops upright. Repeat with the rest of the cake pops. Remember to keep the balls cold, they are much easier to work with. Stick the completed pops in the refrigerator for at least 1 hour before serving. Can be made 1 week ahead.