I'll start with the one we missed the most, Royal China. Lunch or dinner - doesn't matter. Lunch is obviously for the dim sum - which is definitely one of the best in London. You cannot reserve a table and if you arrive a little later than 12.30pm you'll end up queueing for ages. But it is worth it... There are 2 restaurants from the same group located on Baker Street, the other is Royal China Club - a more refined and more expensive version, but also excellent.
Entrance to Royal China, located on Baker Street
My favorites: Dim Sum: Roast Pork Puff (left) - Pork and Radish Dumpling (right)