One can only think of the expression "yum yum :)" when this royal and delicious dish is being talked about or prepared. As the name suggests, it originated in the Mughal era and the lamb is prepared for special occasions, like weddings and parties.
Make slits on the lamb leg using a sharp fork or a knife. Marinate the leg with vinegar, salt, ginger, garlic and cumin pastes for 24 hours in a fridge. During this 24 hour period, take the leg out every 3-4 hours and make slits on the meat or hammer the meat with a sharp fork. This way the ingredients will enter well inside the meat. Do not tear up the meat though, so be careful while hammering or making slits on the meat.
When the leg has been marinated, push in whole cloves of garlic inside the meat. You can dig in a few slits a bit deeper than the others and push the cloves in.
Repeat for the onion slices.
Preheat the oven for 10 minutes at 200 degree Celsius.
Grease the baking tray with 1 tablespoon of oil and place the lamb leg on it. Cover with aluminum foil paper.
Bake for 30 minutes on one side. Repeat again for the other side.
After the first 10 minutes of baking, check if there is any oil coming out of the meat. If you see that there is no oil or melted fat coming out, then sprinkle 1 tablespoon of oil on to the meat. Usually, melted fat is released as oil when the meat gets heated.