Heat oil in a deep pan over medium heat. Add mustard seeds and fenugreek seeds. Once they splutter, add curry leaves.
Add finely sliced onions and sauté until golden brown. Stir in ginger-garlic paste and green chillies for 1–2 minutes.
Add chopped tomatoes, turmeric, coriander, cumin, black pepper, and chilli powders. Cook until the tomatoes soften and the oil separates.
Add the chicken, mix to coat, and sear for 5–7 minutes.
Add water and tamarind paste. Bring to a boil, reduce heat, cover, and simmer for 15–20 minutes.
Stir in coconut milk and garam masala powder. Simmer for 5 more minutes and adjust salt as needed.
Garnish with fresh coriander before serving.
