Place cereal in a large bowl. Place vanilla baking chips in a small microwave-safe bowl. Microwave on HIGH at 30-second intervals until melted, stirring each time. Tint with gel food coloring, if desired.

Pour melted mixture over cereal; stir until coated. Combine powdered sugar and gelatin dessert powder in a large resealable plastic bag. Close bag; shake well until coated with powdered sugar mixture.

If desired, for a rainbow of cereals, repeat making additional batches using a different color gelatin for each batch; combine the different colored cereals. Stir in sour belts candy, if desired. Store in an airtight container.