Wash potato and cook them in a pressure cooker.
Blanch the tomato, make a puree of it.
Soak cashew in hot water.
Take oil in a pan, add cumin, as it crackles put the onion to it. Let cook for sometime, until it is translucent.
Add the tomato puree to it. Let cook for sometime.
Add turmeric powder, coriander powder, chilli powder, cumin powder and garam masala.
Let cook for sometime. Add salt to it.
Remove the skin of the potato and cut them into cubes.
Put some water into the cooked masala, we need a gravy here.
Now, add the potato cubes into it.
Let cook for sometime.
Garnish with fresh coriander leaves.