First, peel off the raw mangoes very nicely. Rinse those off in water and cut into square pieces.
Place the mangoes in a cooker. Add a pinch of salt, 1/2 teaspoon Turmeric (or even less), 1 teaspoon cumin, and coriander powder each. Also, add a pinch of red chili powder (optional).
Pressure cook all the ingredients until 3-4 whistles. After the pressure is released, pour the mixture in a large bowl and allow it to cool down for around 10-15 minutes.
Now, after cooling down, remove the white membranes or any hard skin if present in the mango. Make sure to extract the pulp or the mango flesh only. Place the boiled raw mango mixture in a blender jar.
Add a generous amount of sugar or jaggery powder and some mint leaves. You can also add 0.5-1 tablespoon chat masala into it.
Blend the mixture very well to form a smooth concentrated paste. Avoid using additional water before blending.
Now, take a tall glass. Pour in some of the mango pulp paste (around 2 tablespoons) in it.
Add some ice cubes and water (preferably cold water) into the glasses.
Stir the mixture so that it mixes well in water. Enjoy your chilled glass of Aam Panna.