The Gate? It's on our list to get around to. Hammersmith should be reopening soon, but they have one in Islington as well.
If you want out of the country, go to Dennis Cotter's Cafe Paradiso in Cork. Could be a not outrageously expensive weekend. I took L&W there for consecutive evenings and it was under 40€ a head for 3 course meals with booze each night. Just astonishing food, that happens to be veggie too.
The Gate's not so good these days