[For the filling:] Heat oil in a wok and fry garlic until fragrant. Add onion, cinnamon stick, curry leaves, meat curry powder and potatoes. Add just enough water to cover the potatoes. Cook over a medium low heat until potatoes are done.
Add chicken, salt, sugar, pepper and oyster sauce. Stir-fry until meat is cooked and dry.
Dish out and leave in a plastic colander to drain off excess oil.
[For the pastry:] Put sifted flour into a mixing bowl and stir in salt. Rub margarine into the flour until mixture resembles breadcrumbs.
Make a well in the centre, add water and lemon juice. Mix with both hands to form a soft dough. If dough is a bit dry, add a little more water. Do not knead. Set dough aside to rest for 1015 minutes.
Divide pastry dough into two portions. Roll out each portion to about 1/4 cm thickness. Cut out into 910 cm rounds with a cutter.
Place a tablespoonful of filling in the centre of each round. Fold pastry into half to enclose the filling. Seal by pinching and fluting the edges.
Heat enough oil in a wok and, when hot, deep-fry the curry puffs until golden brown. Remove and drain on absorbent paper.