Marinate the chicken in some salt and ginger-garlic paste whilst you chop and cook the onions-tomatoes.
Heat oil in a heavy-bottomed pot, add in the whole spices and coriander stalks. Stir for a few seconds and tip in the onions with a pinch of salt. Saute the onion for 5 minutes.
Tip in the tomatoes and all the spice powders except garam masala. Saute for a minute. Tip in the marinated chicken and fry for 5 minutes on a medium-high flame.
Add 1/2 cup of water, cover the pot and cook for 6-7 minutes or until the chicken is cooked. In the last 2 minutes add in the cream, garam masala and dried fenugreek leaves. Mix it well.
Till the chicken is cooking make the tempering. Heat oil in a small pan, add in the nigella seeds, let them splutter. Add in the green chillies and fry for a few seconds.
Add in the jaggery, ginger-garlic paste and red chilli powder. Mix well and fry for 2-3 minutes. Keep it aside.
Just before serving add the tempering and garnish it with freshly chopped coriander.
Serve hot with rotis or rice!