In a pan, heat ⅓ cup oil and add 50g butter.
Add 2 medium chopped onions and sauté until translucent.
Add 1 kg chicken and mix well. Cook for 5 minutes on low flame.
Add 1 tbsp ginger garlic paste and mix well.
Add 4 tomatoes, cover with a lid, and cook until soft. Remove the tomato skins and mash the tomatoes.
Add black pepper, cumin powder, crushed chillies, salt, and coriander powder. Mix well.
Add ½ cup yogurt and cook until everything is well combined.
In a separate pan, dry roast cumin seeds, coriander seeds, black peppercorns, and whole dried red chillies. Grind them and sprinkle over the karahi.
Mix well, cover, and cook for 3 minutes.
Add 100 ml cream and mix well.
Garnish with butter, green chillies, lemon slices, ginger, and the remaining ground roasted masala.