1.Marinate the cleaned Mutton with red chilli powder ,turmeric powder, salt & Lemon juice(or Vinegar) and keep it aside for 15 minutes.
2.Now heat oil in a wok. Add curry leaves & fenugreek seeds. Once it has spluttered add Ginger, Garlic & Green chillies. Saute it till you get that fine aroma of garlic.
3.Now add Onion. Saute it till it becomes brown. Add tomatoes. Saute it till it becomes pulpy and is cooked very well.
4. Now add the remaining chilli powder, turmeric powder, coriander powder and garam masala. Saute it for a couple of minutes.
5.Meanwhile cook the marinated mutton partially along with potato. Don't add water. Now add the cooked Mutton & Potato along with the juices running out of it to the Masala gravy. Add sufficient water and salt.
6.Now Cook it closed, till the whole masala covers the mutton pieces completely and reduces in quantity. Stir it occasionally to avoid sticking to the vessel. Serve it hot with the ghee rice or along with chappathi / Naan / Porotta.