Mr. Ho's Chicken Curry

Mr. Ho of the Singapore American School was famous among the students for his chicken curry.  This recipe appeared in the Decembeer 2009 edition of the Singapore American School Journeys, an alumni magazine.  This recipe is said to make 5 servings.  I have provided English equivalent measurements  where metric was specified.  The garam masala was found at Walmart in the spice aisle.  "When we looked up candlenut, we were told that Brazil, hazelnuts, or Macadam nuts could be substituted in recipes.    Because we do not know how big a candlenut is, we haven't been able to determine the quantity of the substitute that is required.
 

2 kg (5 lb) chicken, disjointed
500 ml (17 oz) chicken stock
300gm (10 1/2 oz) chopped onion
4 tbs oil
3 cloves chopped garlic
1/2 tsp ground ginger
4 tsp ground coriander
1 tsp curry powder
2 tsp chili powder
2 tsp tumeric powder
5 tsp garam masala
1 cup coconut
5 candlenutsblended into paste with coconut milk
5 curry leaves
4 peeled potatoes cut into 8 pieces each
2 chopped tomatoes
1 cup plain yoghurt

B;emd all pwder ingredients and the candlenut into a curry pastec.  Heat Oil.  Brown onion and garlic; then add the curry paste, curry leaves, and chicken.  Stir fry until gragrant.  Add chicken stock, potatoes, and tomatoes; cover and cook over a low heat until the chicken is tender.  Add the yoghurt and cook for another 5 minutes.  Salt to taste.  Serve with rice or roti prata.