If you love Thai food and can handle really hot stuff that is so delicious I have eaten it crying (some of it is really hot), then try Spice I Am- easy walk from where you are if you are around Hyde Park. You can't book, but just go and put your name down, they tell you how long and you can go to the pub nearby OR
If you like dumplings, try Din Tai Fung in World Square- walkable from Hyde park and same no booking deal as above..... So, so yummy AND
Yum Cha at the Marigold or East Ocean in Chinatown.
Enjoy!