Mix spice mix, lemon juice, ginger, garlic and yogurt in a bowl. Set aside.
Wash the mutton leg thoroughly, and leave the leg in colander to dry.
Poke the leg all around with a fork.
Then apply spice mixture throughly all over the leg.
Cover with cling wrap and store in fridge over night. (8-16 hours)
Next day, cook the mutton leg in wide pot with 2 cups of water. Keep the heat on medium low and cover the pot tightly to seal the steam.
The mutton leg will take 2-3 hours of cooking time. Keep checking at intervals of 30 minutes and adjust heat as needed.
When mutton leg is absolutely tender. Remove from heat and set aside.
Mix chilli garlic sauce, cream and remaining gravy from mutton leg in a bowl and cover all over the mutton leg.