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Rainbow Dessert (Mosaic Jell-O with Creamy Layer)

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A bright, colorful rainbow dessert made with cubed gelatin and a creamy vanilla layer. This fun "mosaic" Jell-O recipe is a favorite for kids’ parties, St. Patrick's Day, and rainbow-themed activities. Kids love cutting, sorting, and gently mixing the colors!
  • Category: Dessert
  • No Bake
  • Skill Level: Beginner
rainbow jello dessert with creamy layer

Prep: 30 minutes | Chill: 5-6 hours | Yield: 12-16 squares

Ingredients

Rainbow Jell-O Cubes

  • 4–5 small packages flavored gelatin (different colors)
  • 1¼ cups hot water per gelatin package

Creamy Layer

  • 2 packages unflavored gelatin
  • ½ cup cold water
  • 1½ cups hot water
  • 1 (14 oz) can sweetened condensed milk

Instructions

Make the Colored Jell-O

  1. Prepare each flavored gelatin using 1¼ cups hot water only (do not add cold water). Stir until fully dissolved.
  2. Pour each color into a separate shallow container or pan. Refrigerate until fully set (about 2-3 hours).
  3. Once set, cut each color into small cubes.
  4. Gently mix the cubes together and spread evenly in a 13×9-inch pan.

Make the Creamy Layer

  1. In a bowl, sprinkle unflavored gelatin over cold water. Let sit for 3 minutes to bloom.
  2. Stir in hot water and mix until gelatin is fully dissolved.
  3. Add sweetened condensed milk and stir until smooth.
  4. Pour the creamy mixture evenly over the rainbow gelatin cubes.
  5. Refrigerate 5-6 hours, or until fully set.
  6. Cut into squares and serve chilled.

Kid-Friendly Tips

  • Kids can help choose colors and cut gelatin with a plastic knife
  • Let kids gently mix the cubes to avoid breaking them
  • Teach patience- this recipe is all about chilling and waiting!

Fun Variations

  • Add gold chocolate coins on top for a St. Patrick's Day "pot of gold"
  • Use clear cups for individual rainbow desserts
  • Make holiday colors only (red/green, pastel, or patriotic)

Notes

Using hot water only for the colored gelatin makes it firmer and easier to cut. Store covered in the refrigerator for up to 3 days.

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Recipe, image and content from Kids-Cooking-Activities.com