Heat the oven to 350 degrees. Coat a 13x9-inch baking pan with nonstick cooking spray. Combine the cake mix, 3/4 cup sour cream, milk, oil and eggs in a large bowl. Beat at low speed for 30 seconds or until combined. Increase the speed to medium and beat for 2 minutes. Pour into a pan. Bake for 30 to 35 minutes or until a toothpick inserted in the center comes out clean. Cool completely in the pan on a wire rack. Cut the cake in half. Remove and finely crumble half of the cake into large bowl (reserve remaining cake for another use.) Add the frosting and remaining 1/4 cup sour cream. Stir until the mixture is blended (it should be moist but slightly crumbly). Using a 1 tablespoon-scoop, form into 1-inch balls. Place on a wax paper-lined baking sheet. Refrigerate for 2 hours or until set. Melt the candy melts in a microwave-safe measuring cup according to the package directions. To dip the cake balls, insert 1/2-inch of the lollipop stick into the melted candy, then halfway into the cake ball. Dip the cake balls into the candy melts to cover and tap gently to remove excess. Stand upright inserted in a foam block or empty glass until dry. Using decorator pens or frosting, decorate as desired. Let stand until set.