Heat 2 tbsp oil in a pressure cooker and fry the lamb shanks for 1 minute on high heat. Then add salt, ½ tbsp. of ginger & garlic paste and place the lid. Cook till lamb shanks are soft and tender.
Heat 5 tbsp of oil in a large kadhai and add cinnamon stick, cloves, and cardamom. Then add sliced onion and fry till light golden.
Add ginger & garlic paste along with red chili powder, coriander powder, and turmeric powder. Fry on a slow flame for 2 minutes. When the masala sticks to the kadhai, then add sliced tomato, curry leaves, chopped mint leaves, and amchoor powder.
Fry for 1 minute, and then add whisked yogurt. Place the lid and cook the masala on a slow flame for 10 minutes.
Finally, add boiled lamb shanks along with 1 cup of its stock. Taste and add salt, garam masala powder, and chopped coriander leaves. Cook the lamb shanks in the masala for another 10 minutes on slow heat.
Serve hot with Roti or Pulao