I work round the corner and have been a frequent visitor over the years. This place is excellent and has never let me down. Some really good imaginative ideas - for example, the bread starter, a warm brown loaf on a wooden platter with three herb butters. I've always liked the sea bass with ginger and spring onions, or the monkfish and cous-cous. Substantial portions; I seldom bother with side dishes (not their strongest suit to be honest).
Although they do serve meat dishes, the fish is what they're really about. ( In the office we just refer to the place as "The Fish".)
Suggest booking in advance, as it's a small corner-cafe type premises and gets v. busy. Nice bustling vibe.
Not cheap, but top quality.
Back To Basics is an ideal place to enjoy a wide selection of seafood, and booking is required for lunch as the restaurant fills up quite quickly. Catering for private parties of up to 50 guests is available upon request and sating on the pavement is provided.