Peel the mangoes. Its optional but I have always peeled it like my mom.
Now slice it into flat pieces.
Its OK if it gets uneven - it doesn't really matter.
To a pan, over medium heat, add jaggery and 1 cup of water.
This is done to melt the jaggery - takes around 4-5 minutes
Filter this to a cup. This straining is essential to remove any scum or debris (that's mostly found in jaggery). Keep aside.
In the same pan, add the Ghee and when hot, drop the mustard seeds. Add Red chillies if using.
When it starts spluttering, add the mangoes.
Stir gently for few seconds. Add turmeric, if using.
Add about 1-1/2 cups water
cover and cook for around 5 minutes.
Remove the lid, give it a gentle stir and without the lid continue cooking for another 8-10 minutes or until it starts becoming mushy.
Now add the Jaggery water,
stir and simmer further for another 10-15 minutes,
until it comes together into a thick sauce. The consistency will depend on your family's preference. If it becomes too thick for your liking, add few tbsp of water to rectify it.