One of the benefits of living in central London is that you are able to explore the city's nooks and crannies and find neighbourhood restaurants that people passing through - even those who work there - may overlook. I'm one of the latter - I work in London but commute in, and so only know the area around my office and the main streets elsewhere (think Upper Street, Wardour Street and so on). One of my friends lives in Bloomsbury and she stumbled across a gem of a local restaurant on Tavistock Place:
Pizza Sophia.
It's one of those restaurants that barely has a website (it just has the address and phone number), only has a handful of tables at street level (with more downstairs) and you'd almost walk past it if you weren't looking for it.
My friend has been a couple of times now and said the pizzas were amazing and she wasn't far wrong. They are absolutely huge, clearly homemade and smothered in delicious toppings - for instance the menu states that the restaurant smokes its own meat. There is a wide choice of pizzas and some pasta on the menu and they were happy to cater for my vegan friend by altering some of the toppings.
I had the New Yorker, which was a steal at £9 for a giant pizza, with smoked beef brisket, pepperoni, caramelized red onion, mozzarella and tomato. It was delicious and I barely managed to finish it. I spotted takeaway boxes on the way out so if you don't manage to finish the pizza you can ask for the rest to go!