1.Mix the gelatin and water in a small bowl until it thickens and then microwave it for 10 seconds.
2.Mix 1/4 cup sugar, milk, and vanilla extract in a medium pan over low heat. Stir until the mixture starts to simmer, and then add the gelatin mixture. Whisk until well combined.
3.Fill a medium bowl with ice cubes ⅓ of the way full and then place another empty bowl on top of the ice. Use a sieve and strain the milk mixture into the empty bowl, and then add the heavy cream and whisk until thickened.
4.Now transfer the mixture evenly into four glass dessert cups, cover tightly with plastic wrap, and place in the refrigerator for 2 hours.
5.Combine the diced mangos from 1 mango, 1 1/2 tablespoon sugar, lemon juice, and orange juice in a medium pan over medium heat and stir until the mixture begins to boil.
6.Blend the mixture with an immersion blender until smooth. Turn the heat down to low and bring to a simmer, then turn the heat off. Transfer to another container and move to the refrigerator and chill for 1 hour.
7.Pour the chilled purée over the panna cotta, top with diced mango from the last mango and fresh mint. Serve immediately and enjoy!