Cut the mutton into medium sized pieces. Wash and drain. Keep aside.

Wash the chana dal in 2-3 changes of water or till the water runs clear. Cook with 2-3 cups of water to which a little salt and 1/2 teaspoon turmeric powder has been added. The dal should be tender but not mushy or else it will turn into a paste once you add it to the curry, so take care to keep an eye out as it cooks.

In a pressure cooker heat some oil and fry the onions till golden-dark brown (but not black, so take care not to burn them). Drain and set aside. Once cooled they will turn crisp. You may also deep fry the onions to achieve the same result or even use store bought browned onions.

Add some more oil to the pressure cooker if required and on medium-low heat, fry the green and black cardamoms, cloves, cumin, cinnamon or cassia bark, bay leaf, peppercorns for a few seconds. Toss in the kasuri methi too for a quick few seconds.

Add in the garlic paste, julienned ginger and tomato paste and stir fry. Next, add half the fried onions and chopped tomatoes and fry for half a minute.

Toss in the powders - turmeric, chilli, cumin, coriander and garam masala and continue to fry on a low heat. Now add the meat and fry for about 3-5 minutes

Add the mint leaves, 1-1/2 cups of water and salt to taste. Cover the pressure cooker, place the weight (whistle) and cook until the meat is tender (I normally cook mutton on full heat until the first whistle goes off, then reduce the heat completely and continue to cook for 10-12 minutes. Then let the cooker cool down a bit until the whistle releases easily. Open and check, if the meat is not tender, cover and cook again for another 5 minutes on a low heat till done)

Add the pre cooked chana dal, the rest of the fried onions, coriander leaves, green chillies and mix everything. On a medium heat cook until the gravy starts to thicken.

Remove from heat, garnish with ginger julienne and slit green chillies (optional). Serve hot with rotis, chapathis, naan or rice