Combine mango, watermelon, sugar syrup, and lemon juice in a food processor until smooth.

Pour the mixture into an ice cream maker and churn until it reaches the right consistency.

If an ice cream maker is not available, pour the mixture into a wide pan and freeze until solid.

Break the frozen mixture into pieces and grind using a food processor.

To make mango puree, combine mango, confectioner sugar, and lemon juice in a food processor and grind until smooth.

Cool the mango puree for at least 2 hours before use.

To make lemon-mint jello pyramids, grind mint leaves, sugar syrup, and lemon juice in a food processor.

Bring water to a boil in a saucepan, then pour into a bowl and add gelatin, stirring with a fork.

Add the mint-lemon mixture to the gelatin mixture, and pour into a pyramid or ice cube mold.

Freeze the jello pyramids for 30 minutes.

Serve the sorbet as is, or with mango puree and lemon-mint jello pyramids.