Prepare the fresh spice blend: Dry-roast the cumin seeds, fennel seeds, and coriander seeds (if using whole) in a small pan over low heat for about 1 minute until fragrant. Let them cool, then grind into a fine powder. Mix with the black cardamom powder and coriander powder. Set aside for the end.
Fry and blend the base: Heat the oil in a pressure cooker over medium heat. Add the sliced onions and sauté until light golden brown, about 5–7 minutes. Add the chopped tomatoes and fry for 2–3 minutes until softened. Remove from heat and use an immersion blender to blend everything into a smooth paste right in the pressure cooker.
Bhunai part 1 - fry the meat: Add the meat, ginger paste, garlic paste, bay leaf, cloves, and black peppercorns to the blended paste. Add 1 tbsp salt, 1 tsp turmeric, and 1 tsp cayenne. Fry over medium-high heat for 15 minutes, stirring occasionally, until the meat is well seared and coated in the spice paste.
Bhunai part 2 - add yogurt: Add the 2 tbsp yogurt and 3 whole deseeded green chilies. Continue to fry for another 15 minutes on medium heat, stirring occasionally, until the oil begins to separate from the spice paste at the edges. DO NOT skip or rush this step.
Pressure cook the meat: Pour in 4 cups of water. Close the pressure cooker lid and cook for about 10 minutes until the meat is almost tender — nearly cooked through but not falling apart.
Add the potatoes: Carefully release the pressure and open the lid. Add the halved potatoes to the curry. Cover and simmer on medium heat for 15–20 minutes until the potatoes are fully tender and cooked through, and a thin layer of oil (rogan) has risen to the top.
Finish with the spice blend: Sprinkle the prepared fresh spice blend evenly over the curry. Stir gently to combine. Turn off the heat.
Garnish and serve: Top with fresh chopped coriander, julienned ginger, and finely chopped green chilies. Serve hot with naan, roti, or basmati rice.