1/2 cup frozen mango chunks (about 2 ounces), plus more for garnish
Maraschino cherries, for garnish
Pour the tropical juice and coconut milk into separate ice cube trays and freeze. Peel the banana, cut into chunks and freeze on a plate.
When you're ready to make the drinks, add the frozen juice and coconut milk cubes to a blender with the banana chunks. Add the pineapple, rum and mango and blend on high until very smooth, light and creamy, scraping down the sides of the blender several times, 1 to 2 minutes. Immediately pour (or pipe for a soft-serve look) into 4 glasses. Garnish with mango chunks and maraschino cherries and serve.