Might also try a couple British burger chains, such as Wimpy, GBK or Byron.
This was my last trip report from London. Time is flying. Sadly, Bonnie Gull closed its 2 locations. [London , Covent Garden, Soho and Bloomsbury] Rules, Ivy Soho Brasserie, Zima, Bonnie Gull Seafood Shack, GAIL's Kitchen