To make the sauce place the tamarind and 200 ml warm water in a bowl and set aside for 15 minutes. Then gently rub the tamarind, separating the pulp from the stones. Strain through a coarse sieve and discard the fibre and stones.
Mix in the sugar, 1 tsp of salt, garam masala, chilli powder to taste and sultanas. Simmer together gently for 8 minutes then remove from the heat.
Trim the duck breast of sinews and score the skin into diamonds. Mix 1 tsp salt with the five spice powder and rub into the duck breasts.
Place the duck breasts skin side down in a frying pan over a low heat. As soon as the fat in the skin begins to melt increase the heat to medium and fry for about 5 mins.
Turn the duck breasts over and continue frying until cooked. The duck will be pink inside after a further 5-6 minutes but if you want it cooked more fry for 2-3 minutes longer.