Preheat oven to 350°F. Grease 3 (6-inch) round cake pans and line with parchment paper. Grease again or spray with non-stick cooking spray. Set aside. Place all of the CAKE ingredients (including cake mix) in a large bowl. With an electric mixer, stir on low speed to combine (30 seconds). Then turn mixer up to medium and beat for 2 minutes. Divide batter evenly into the 3 prepared cake pans. Bake in preheated oven for 40-50 minutes or until a toothpick stuck in the middle of the cake comes out clean. Let cool. Level the cakes by cutting horizontally to remove the domed tops. Reserve the cut pieces of cake and crumble into a bowl. Add about 1/2 cup of frosting. Stir into crumbs until combined. Form into 2-3 large cake balls (about the size of a scoop of ice cream). Place in refrigerator to chill for about an hour.
Melt the white chocolate according to package instructions. I did it in the microwave. Be careful not to overheat. Microwave for 20 seconds. Stir. Then microwave for 10 seconds. Stir until smooth. Add a teaspoon of oil. Stir. Dip the ice cream cone in the melted white chocolate then add sprinkles. Put on a parchment lined cookie sheet and put in refrigerator to harden. Dip a lollipop stick into melted chocolate, about 1/4 inch down. Stick in middle of cake ball. Repeat with remaining cake balls. Set aside. (Note: You only need one cake ball for the cake, but have extra in case you mess up or have taste testers that want to eat them.)
A note about serving. You can either have 12 big slices of cake or 24 small slices of cake. To get 24 servings, slice the cake (like a pie) into 12 slices. Then cut each of the slices into 2 servings.