1. Put the mangoes, lemon juice, and salt in a large saucepan, set over medium heat, and cook, stirring occasionally, until the mangoes are very soft, about 5 minutes.

2. Add the sugar and continue cooking, stirring and scraping the bottom of the saucepan, until the mixture becomes thick and syrupy, with a few chunks of mango remaining, about 15 minutes. Do not let the sugar caramelize and brown. Remove from the heat and cool to lukewarm.

3. Stir the gelatin into the mango mixture until it dissolves, then stir in the cream until well incorporated.

4. Divide the mixture among eight 4-ounce ramekins or serving bowls. Chill in the refrigerator, uncovered, until set, about 3 hours. Serve cold, with chantilly on top, if desired.

For the Chantilly: Whisk the cream until soft peaks form. Add the sweetened condensed milk and salt and whisk until medium-soft peaks form. (When you lift the whisk from the cream, a peak should form and the very tip should fall back down.) Makes 2 cups