45 Jermyn St.
A sophisticated crowd enjoys the sumptuous and elegant decor at this classic brasserie at the back of the royal grocer, Fortnum & Mason. An old-school trolley arrives table-side to serve Siberian sturgeon caviar with scrambled eggs, baked new potatoes, and blinis, while creamy beef Stroganoff and whole duck with elderberry sauce get the full table-side-flambé treatment. Truffles that are shaved at the table are another specialty. The popular Welsh rarebit toasty has a punchy mustard kick, while nostalgic desserts include a fleet of alcoholic ice-cream floats. It's open all day, with an unusually long five-hour window for lunch bookings—perfect if you want to take a break from shopping nearby.