Watermelon Jelly: the recipe for a fresh and colorful Sicilian dessert

1. Remove the seeds from the watermelon pulp and blend it in a blender.
2. Pass the mixture through a sieve to obtain 500 ml of juice.
3. Blend 1/3 of the juice with the cornstarch until smooth.
4. Pour the remaining watermelon juice, the cornstarch mixture, and the sugar into the saucepan.
5. Stir over heat for 5 minutes or until thickened.
6. Pour the gelatin into the molds and let it solidify in the refrigerator for at least 5 hours.
7. Turn the gelatin out onto a plate and garnish with chopped pistachios.