Skin the chicken if required and cut into bite sized pieces.
Heat the oil in a saucepan and gently fry the onions for 2 – 3 minutes until beginning to soften. Add the peppers and cook for another 2 – 3 minutes then stir in the chopped garlic.
Stir in the garam masala,cumin, ground coriander, turmeric, dried chilli, ginger and fresh or chilli paste and stir well.
Add the chicken pieces and stir to coat in the spice mixture and continue cooking the chicken until it has changed colour, stirring frequently.
Stir in the water and add the stock cube. Then stir in the chopped tomatoes, tomato purée and sugar. Bring to the boil, stirring constantly then reduce the heat and simmer gently for about 30 minutes.
Season to taste with salt and pepper, stir in the chopped coriander and serve.
Cook's TipIf you are in a hurry you can reduce the final cooking time by 10 minutes, however I think the flavour improves if you give the flavours time to blend, so if time permits you can also cook for another 15 to 20 minutes or so. Add a little water if the mixture starts to get too dry.