More than 1,000 reservations were made within 48 hours of the reservation lines opening for 23 August to 19 September, during which time all food will be offered with a 50% discount.
The new 80-cover restaurant and 40-cover bar forms part of a £15m refurbishment of the 165-year-old boutique property owned by Veladail Hotels.
Henrik Muehle, general manager of Flemings Mayfair, said the bookings came "flying in" as soon as details of the soft launch was announced. "We're delighted that diners are sharing our excitement about the upcoming launch of Ormer Mayfair and Shaun Rankin and the team can't wait to get started."
Dishes on the menu will reflect Rankin's Jersey heritage and include hand-dived scallops from the Channel Islands; Jersey lobster ravioli in a crab and lemongrass bisque; seasonal venison loin with Medjool dates, quinoa, parsnips; and chocolate tortellini and double chocolate brownie with salt caramel and milk ice cream.
Rankin will continue to run Ormer in Jersey as well as his new restaurant in Mayfair. Ormer Jersey was launched in St Helier in 2013 after Rankin had spent nine years as head chef at the island's Bohemia restaurant. Bohemia gained a Michelin star in 2005, with Ormer Jersey receiving a star four months after its opening.
Rankin's right hand man in the Mayfair kitchen will be head chef Kerth Gumbs, while the roles of restaurant manager and sommelier will be filled by Agnieszka Josko and Andreas Rosendal respectively.
Originally launched as a hotel in 1851 after being converted from 13 Georgian townhouses, Flemings Mayfair is a member of Small Luxury Hotels.
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