Clean the liver and soak in milk overnight. Drain and dice.
Heat butter or oil in a frying pan, add cumin seeds, cardamom, cinnamon, peppercorns.
When the cumin seeds starts to sputter add the chopped onion and garlic.
Cook over medium heat until the onions are translucent and glossy. Dissolve coriander powder and turmeric powder in two tbs. water and add to the pan. Stir until the moisture evaporates.
Add tomatoes and salt. Stir-fry until the oil floats on top.
Add liver and spring onion greens. Cook until liver becomes tender.
After that keep on stirring the masala till the color of the liver & masala turns reddish brown.