Wash medium-sized tomatoes and cut them in a criss-cross manner at the bottom using a sharp paring knife.
Heat water in a pan over high heat. Once the water comes to a boil, add the tomatoes to the pan.
Cover and cook for 3-4 minutes. Remove the pan from heat and let the tomatoes cool down for 10-15 minutes. Take out the tomatoes from the water using a tong and discard the water. Peel the skin of the tomatoes by pulling them from the bottom cuts. Set the peeled tomatoes aside.
Heat ghee in a pan over high heat.
When the ghee is hot, add bone-in mutton (cut into 1 and ½ inch pieces) and salt and saute for 4-5 minutes.
Reduce the heat to low. Cover the pan with a tight-fitting lid and cook for 20-25 minutes. Stir a few times in between.
Add the peeled tomatoes, green chilies (slit into half), chopped ginger, and chopped garlic to the pan and mix well.
Cover the pan again and cook for another hour or until the mutton is tender. Keep mashing the tomatoes using the back of the ladle a few times while cooking. By the time mutton is cooked, tomatoes should be mashed well and integrated into the curry.
Garnish with chopped cilantro (coriander) and serve hot with roti.