Kerala Chicken Curry recipe

Ingredients
15  medium sized pieces (about 800  grams) of chicken
2  medium onion(s) sliced
2  cup(s) grated coconut
8  cloves garlic
1  tablespoon(s) each of coriander and red chilli powders
1  tablespoon(s) juliennes of ginger
2  green chilli(es) slit
2  whole red chilli(es)
1  teaspoon(s) turmeric powder
12  curry leaves
2  tablespoon(s) oil
2  cup(s) water
salt to taste
finely chopped coriander leaves for garnishing (optional)