In a bowl, marinate the lamb pieces with yogurt, garlic, ginger, cumin powder, coriander powder, turmeric, salt, and pepper. Let it marinate for at least 30 minutes or overnight in the refrigerator for best results.
In a large pan, heat the vegetable oil over medium heat. Add the chopped onion and cook until soft and translucent.
Add the marinated lamb to the pan and cook until browned on all sides.
Pour in the cream and stir well to combine. Cover the pan and let it simmer for about 30 minutes, stirring occasionally.
Once the lamb is cooked through and the sauce has thickened, sprinkle garam masala over the dish and give it a final stir.
Serve hot, garnished with chopped fresh cilantro.
Enjoy!