Make a paste using the ginger and garlic paste, turmeric, curry and chilli powder and add a little water.
Fry onions in a little oil until soft. Add the paste and fry for a few minutes. Add chicken and fry until browned.
Add coconut milk, tomato puree and stock. Bring to the boil. Simmer for 15 to 20 minutes.
Sprinkle in garam masala for final 2 minutes of cooking time.
I use coconut milk but it can be made using yogurt instead. As with all curries, taste while cooking and add more chilli powder if needed! Also the same with the coconut milk - start by adding the 200ml, but add more if the curry is too hot.