A great place to start the day if you are in South London is Federation Coffee in Brixton Village. The food is great and so is the coffee. This is a very chilled place where you can get both and indoor and outdoor experience (even though the whole place is under the Village roof).
It's really close to my house and one of my favourite pubs in London! (I even went before it was close to where I lived!) It is London's first cooperatively owned pubs and has lovely events and workshops, exercise classes and great parties, and good beer! It's lovely in the beer garden in the hot summer and equally great in the winter, next to a real fire.
St. JOHN is famous for its 'nose to tail' dining which encourages people to eat ‘unusual’ parts of the animal. St. JOHN also have their own bakery and winery and you can just visit for a drink and small bite in the bar (Clerkenwell and Spitalfields).