Ingredients:

•  4 large              Unripe Mangoes (kacchi kairi)
• 5 tbsp                Sugar
•  1 tsp roasted    Cumin Powder (bhuna jeera powder)
• 1/2 tsp               Black salt
• 1/2 tsp               Salt

Method:

1. Rinse and then wipe dry the mangoes. keep a Tawa or roti rack or papad rack on a gas stove top.
2. Place the mangoes on it. keep on turning them at intervals so that they are charred and cooked evenly.
3. The peels should get charred. To check doneness, slid a knife on one of the sides and the knife should slid easily without any resistance. 
4. keep the roasted mangoes aside and let them cool at room temperature. you can also keep them in water for some minutes and then peel them.
5. once they cool down, then remove the charred peels. Remove the peels well. Discard the seeds.
6. Mash the mangoes to take out all the pulp. Do not discard the water.
7. Add 5-6 cups of water in the existing water.
8. Add  sugar, roasted cumin powder , salt and black salt to the mango pulp mixed with water.
9. Mix well to dissolve the sugar. Adjust sugar and salt according to your taste.
10. Add more water if required. Chill it for a few hours before serving.
11. Pour the panna in glasses.
12. Add some ice cubes.
13. Garnish with mint leaves.
14. Serve chilled.