Berkeley Square House, 4-19 Berkeley Square, Mayfair, London W1J 6BR
This Mayfair restaurant is an offshoot of the Spanish original which caused a sensation when it opened in Madrid. Designed to look like a rainforest, the restaurant looks like nothing else in London. Food is "a blend of tropical and Latin American cuisines" - so that means everything from Peruvian sushi to South American chupe and a lot of Josper-grilled meats.
A top Japanese izakaya in Mayfair - if you're looking for excellent sushi without the Mayfair prices, this is the place you come. Chef Takamasa Mogi was previously at Nobu and goes big on omakase where you let him choose what to feed you.
The kind of restaurant you're as likely to find yourself sitting next to royalty (it was a favourite of The Queen) as you are a Cork Street art dealer. Run by the ebullient Gavin Rankin and tucked away in a mews off Berkeley Square, it looks like it's been here forever rather than being there just a couple of decades. Make sure to have one of their great matinis in the bar while you're there.
Mayfair's Shepherd Market is the site of this dinky all day Japanese bar, with an ex-Novikov Head Chef in charge, serving up gyoza, soft shell crab salads and green pancakes for breakfast.