To make the marinade, peel and finely chop the onion, ginger and garlic and put them into a blender with ½ teaspoon salt, ½ teaspoon cayenne pepper, ½ teaspoon black pepper and 3 tablespoons water. Blend to a smooth paste, pushing down with a rubber spatula when needed. Cut the chicken breasts crossways into 3mm ( in thick) slices and put in a bowl. Add the marinade and mix well. Cover and refrigerate for 30 minutes, or up to 3 hours if desired.

Peel the onions and slice into fine half-rings. Pour 3 tablespoons oil into a wide, non-stick pan set over a medium–high heat. When the oil is hot, add the cinnamon stick and cardamom pods. Stir for 10 seconds, then add the onions and fry, stirring at the same time, for 6–7 minutes or until the onion turns a reddish-brown colour. Add the cumin and coriander. Stir once. Add the natural yoghurt, a tablespoon at a time, and stir until it is absorbed. Add the tomato and stir for a minute.

Reduce the heat to medium, add the chicken, together with its marinade, and cook, stirring, for 3–4 minutes or until all the chicken pieces turn white. Add 175ml (6fl oz) water, the salt, garam masala and lemon juice. Stir and bring to a simmer. Reduce the heat to low and cook, uncovered, for 2–3 minutes, stirring now and then.