London Restaurants in West End, /Camden and across the Bridge
I'll be visiting across the pond in January (only for 3 days) and am staying in Leichester Square. This will be my third visit to the city so I'm somewhat familiar and very much unfamiliar with the different areas. The last time I visited I basically got stuck with all the restaurants within the Square, the one Mexican restaurant, a small Italian place off to the side and restaurant where I painfully paid 24 pounds for fish, chips and mushy peas. :)
I'm really interested in any small, neighborhoody, popular places across London Bridge toward the Gherkin (there's the food market I'd like to visit) and this particular trip I'd like to dedicate the entire day at Portobello Market which I was never able to visit previously.
More pub or gastropub fare and modernist cuisine if possible, less Indian or kebaberies if possible. TIA
If you want to dine near the Gherkin, you will be in the City, a/k/a the financial district. As such, it mostly shuts down on weekends. If you are there during the week, the restaurants are filled with "men who lunch" and you will need reservations wherever you go (but that's mostly true all over London). There are some fine restaurants nearby though, like Coq d'Argent, Prism, Balls Bros., Barcelona (Tapas), the very old and stately Bolton's or the new and hip Gaucho. I enjoyed a recent meal at Le Paris Grill, known for the hundreds of cut-off ties hanging on the walls as well as for its French food. Spitalfields is adjacent to the City and is home to St. John's Bread and Wine, one of our most fond meal memories from our recent trip. Enjoy your three scant days in London!
Firstly, mush, a little local geography. The Gherkin is about 1/2 a mile north from the northern end of London Bridge, and Borough Market is about 3 minutes walk from the southern end. The market has more places operational towards the end of the week. The notable building near the market is the unfinished Shard.
As for feeding yourself, Borough Market has many options, from sandwiches to some quite smart restaurants. They're all pretty good, but fairly pricey (not £24 for fish and chips pricey though!). My choice would be Wright Brothers for some seafood, but you should look around the whole market before deciding.
Edit: Unless you mean Leadenhall Market, which is quite close to the Gherkin? Worth a visit, but much more a shopping mall than a food market.