pressure cook the mangoes with water, till they are soft.
Let the mangoes cool down completely. After that peel them and discard the seeds and peel.
Now mash the Mangoes with a hand blander to make a smooth pulp.
Add Jaggery, cumin powder, black pepper powder, Rock salt into mango pulp.
Blend them to a smooth mixture.
Take 1/4th of panna syrup and 1 cup water into serving jar with lots of ice to make an awesome mango panna drink.
Serve chilled.