Cut each fruit, the cucumber, and the jicama into 1/2-inch cubes. Keep them grouped by ingredient on the cutting board.
For best results – One ingredient at a time, sprinkle some chili pepper over the cubes and gently toss on the board to coat. Toss the drier ones first (jicama, pineapple, mango, dried mango) and finish with watermelon and cucumber so the spice doesn’t slide off. Transfer each batch to a large mixing bowl as you go.
DO NOT USE MORE than 2 tsp unless you want.
Add the lime juice and cilantro. Gently fold everything together. Taste and adjust. More lime if it’s flat, more spice if you want more heat.
Whisk the Mexican crema and Greek yogurt together. Add warm water a tablespoon at a time until it’s pourable.
Plate the salad. Drizzle the crema over the top. Garnish with shredded mint, chili pepper, and/or tajin.