01 - Preheat oven to 350°F. Thoroughly grease and line a 9x13-inch baking pan with parchment paper to prevent sticking.
02 - In a large mixing bowl, combine cake mix, eggs, vegetable oil, and water. Beat until completely smooth, approximately 2 minutes. Pour batter evenly into prepared pan and bake according to package directions, typically 25 to 30 minutes. Test doneness by inserting a toothpick into the center—it should emerge clean. Allow cake to cool completely to room temperature.
03 - Break the completely cooled cake into large chunks, then crumble into fine crumbs using clean hands or a fork. Transfer to a large mixing bowl.
04 - In a separate bowl, beat softened cream cheese with powdered sugar (if using) until completely smooth and creamy, approximately 1 to 2 minutes.
05 - Add the cream cheese mixture to the cake crumbs. Mix thoroughly with a spatula or clean hands until well combined and a dough-like, moldable consistency forms. The mixture should hold together when squeezed.
06 - Using a tablespoon or cookie scoop, portion out approximately 1 tablespoon of mixture. Roll between palms to form smooth, uniform balls about 1 inch in diameter. Arrange on a parchment-lined baking sheet, spacing evenly apart.
07 - Place the baking sheet in the freezer for 20 to 30 minutes, or until cake balls are firm to the touch and hold their shape well. This step is crucial for successful coating.
08 - Combine white chocolate chips with coconut oil (if using) in a microwave-safe bowl. Microwave in 20-second intervals, stirring thoroughly between each interval, until completely smooth and fluid. Be careful not to overheat or the chocolate may seize.
09 - Using a fork, gently dip each chilled cake ball into the melted white chocolate, ensuring complete coverage. Lift and tap fork against bowl edge to allow excess coating to drip off. Transfer to a fresh parchment-lined baking sheet. Work quickly as the coating sets rapidly.
10 - Immediately after coating, while chocolate is still wet, sprinkle red or pink sprinkles over the truffles for garnish. This step must be done before the coating hardens.
11 - Refrigerate the coated truffles for at least 30 minutes, or until the white chocolate coating is completely firm and set. Truffles should hold their shape when handled.