Sprinkle the chicken on all sides with half teaspoon salt and generous amounts of black pepper. Pat in and set aside.
Put the apricots in a small pan with 250 ml/8 fl oz water and bring to the boil. Lower the heat and gently simmer for 15 minutes, or until the apricots have softened but are ï¬rm enough to be cooked again later. Leave in their liquid.
Put the oil in a large frying pan or sauté pan and set over a medium—high heat. When hot, put in the cinnamon sticks and cumin. Ten seconds later, put in half the chicken pieces and brown them on all sides. Transfer to a bowl. Cook the remaining chicken in the same way. Add to the bowl.
Add the onions to the pan. Stir and fry until they brown at the edges. Add the ginger and stir for a few seconds. Add the tomato purée and stir once. Now return the chicken and all the accumulated juices to the pan, along with 350 ml/12 fl oz water and 1 teaspoon salt. Cover and bring to the boil. Lower the heat and cook gently for 15 minutes, turning the chicken once during this time.
Remove the cover and add the sugar, vinegar, apricots and their cooking liquid, garam masala and cayenne pepper. Stir and cook over a high heat until the sauce is a bit syrupy.