The restaurant closed in January and will reopen for soft launch this month with a new look and menu. The full transformation will be completed this spring.
It is the second revamp of a Roux restaurant in six months.
Roux at Parliament Square, which is headed up by MasterChef: The Professionals winner Steve Groves, reopened last August with a modernised dining room and a new menu.
A PR statement announcing the reopening said the new Roux at The Landau will ‘reframe the ways in which today’s customers are able to experience the world of fine dining’.
The dining room will feature a new central curved counter displaying charcuterie and shellfish that can be ordered as starters or a light main course, alongside ‘snacks’ such as beetroot tartare and Cornish crab salad.
Michel Jr and head chef Nicolas Pasquier have created a new menu focusing on ‘simple, elegant’ ingredients and classic French cooking techniques.
Dishes will include XL Orkney scallop with Ivy House farm butter and Oscietra caviar; and Cotswold White chicken gyoza with monk’s beard and lemongrass. Desserts will be created by The Langham's executive pastry chef Andrew Gravett.
Roux at The Landau opened in 2010 as a partnership between The Langham, Michel Jr and his father Albert Roux.
Michel Jr also oversees the food at the hotel's Wigmore bar, which opened last year.