Chop the mutton liver into small, bite-sized pieces.

In a bowl, combine the chopped liver with ginger paste, garlic paste, chili powder, yogurt, garam masala, and salt. Mix well to ensure the liver is evenly coated with the marinade.

Let the liver marinate for at least 30 minutes to allow the flavors to infuse.

Heat canola oil or butter oil in a pan over medium heat.

Add the grated onion to the hot oil and saute until golden brown, stirring frequently to prevent burning.

Add the marinated liver mixture to the pan and saute until the fat starts to separate from the mixture.

Add 1/2 cup of water to the pan.

If using a pressure cooker, close the lid and cook for 5 minutes under pressure. Otherwise, cover the pan and cook until the liver is tender, checking occasionally to prevent sticking.

Once the liver is cooked through and tender, uncover the pan and stir-fry to dry any remaining water. Continue stir-frying until the oil starts to ooze out on the edges.

Garnish with fresh coriander leaves and lemon wedges.

Serve hot as a side or main dish.