Chop and grind, the ginger and garlic together, to make a fine paste.
Add the remaining marinade ingredients, along with mutton and mix well. Leave it, to stand unrefrigerated, for 3-4 hours or overnight in fridge(bring to room temp before cooking).
Remove the meat from the marinade and put the marinade aside.
Heat oil and ghee in a pan, over high heat. When hot, add the meat, salt and sugar. Stir and fry for 8-10 minutes, until the meat is lightly browned.
Reduce the heat to very low. Add the marinade.
Cover and cook for 1 hour or until the meat is tender.
Add the green and red chillies. Cook for a further 5-10 minutes.
Add the kewra water, stir and serve with rice or phulka.