I've tried a number of Malaysian food around Sydney and they have been quiet disappointing as there wasn't must flavour in their dishes, but Sedap is one of the best restaurants that serves hawker style Malaysian food.
I ordered the Penang Char Kuey Teow, which is a flat rice noodle stir fried with prawns, fish cakes, Chinese sausage, bean sprouts and severed with a side of sambal (which really has a kick to it). I also ordered a mug of iced Teh Tarik (pulled tea), which was delicious.
If you haven't tried Malaysian food before, then you must try Sedap in the city.

Approximate cost: $15