In a pot add in the water.
Slit the tomatoes on the top. Just give a light cross cut so it is easy to peel off the skin.
Boil this in water for 5-7 minutes.
You would see the skin coming off.
Switch off and let it rest for 5 minutes.
In a plate, remove the tomato and remove the skin.
Discard the skin and roughly smash the tomatoes.
One can puree too if you do not want the chunkier pieces.
Now add the mashed tomatoes back to the water.
Freshly ground the cumin and black peppercorns in a motor or pestle or using a mixer.
Add in the freshly grounded mix, curry leaves, salt to the tomato mix.
Let this boil for 7-8 mins.