Wash the brain thoroughly and boil it in water with some salt and turmeric.
Remove the brain from the water.
Heat oil in a frying pan and add chopped onions.
Sauté the onions till they turn slight golden brown.
Add red chilli powder, a pinch of turmeric powder, coriander powder, garam masala, salt, ginger garlic paste . Stir well and and fry for about 10 minutes, adding a little water if required.
Add the brain and shake the pan gently to mix the brain with the spice mixture. Avoid stirring with a spoon(The brain can also be scrambled if required).
When the oil separates from the spice masala, add chopped coriander, lemon juice.
Serve hot with roti, naan or bread.