I highly rate yum cha at Palace. They offer a great selection of savoury dishes and desserts.
Ask for their special crab/scallop siew mai. They offer regular ones too but this is worth a try.
For dessert, try the mango soup with sago.
Service is a bit hit-and-miss so it really depends on who you get. Come for an early lunch or you could be waiting awhile for a table.