The five restaurants I’d recommend would be Dishoom (cause you have to), one of the Ottolenghis for lunch or an easygoing dinner, a gastropub like Prince Arthur (hot4u) or Plimsoll (four legs), a Turkish ocakbasi, maybe Mangal 1 or Antepliler and a chippy. I think for tourists visiting London this gives a good taste of what London is offering, not necessarily its best places but its most London places.