Peel and slice the mangoes to 2-inch pieces. Keep the stones as well.
Grind the grated coconut with cumin seeds, peppercorns, and the green chillies in a blender.
Grind to a fine paste by adding a little water at a time. Keep this aside.
Give the yoghurt a quick blitz in a blender.
This will break the thick yoghurt to a much thinner consistency.
This will also separate the butter if you are using a full-fat yoghurt.
We don't need this butter for our Mambazha Pulissery. You can store this butter for later use.
Add the mango pieces, turmeric powder, salt, and curry leaves in a pot.
Add just enough (or a little less) water to cover the mangoes.
Mix well and cook on a medium flame with the lid on.
Stir occasionally so that the mango pieces do not stick to the bottom of the pan.
Once the water starts to boil, open the lid, and continue cooking on a low flame until the mangoes are done.
Now add the ground coconut paste to the pot and combine well.
Cook on a medium flame until boil.
Now add the whisked yoghurt.
Mix well and continue cooking.
Now you have to stir frequently and not allow the curry to settle.
This will ensure that the yoghurt doesn't split/curdle.
Bring to boil.
You can reduce a little.
Switch off but continue stirring until the temperature of curry reduces and is not boiling.
In a separate pan, heat some oil and temper the mustard seeds.
Once they start to pop add the fenugreek seeds as well.
Add the curry leaves and finally the dry red chillies.
Let this rest for a few minutes to cool down before adding to the curry.
Serve with some hot, steaming rice.