London bar to serve giant mimosa with whole bottle of champagne for Supergirl premiere week

A bar overlooking Leicester Square is introducing a supersized version of the mimosa cocktail, made with an entire bottle of champagne, to coincide with the London premiere of Supergirl on 18^th June. Rocket Room, which sits above Market Place Food Hall Leicester Square, will serve the drink, named the Jason Mamosa, from 19^th to 25^th June – the same week that Hollywood actor Jason Momoa is expected to attend the premiere on the square below.

The cocktail is a larger take on the classic, served in a fishbowl glass and made with orange juice and a full bottle of sparkling wine. Customers can choose between Pol Roger Brut Réserve NV at £138, Saint Gall Tradition Premier Cru at £80 or Prosecco Acquerrello DOC at £42. The venue says the tipple is available only by advance booking during the one-week run.

The launch coincides with the arrival of Supergirl, when Momoa is expected to appear on the red carpet in Leicester Square. Rocket Room, which overlooks the area, offers a vantage point to watch major film premieres taking place. It opened earlier this spring and combines social gaming with cocktails and DJ sets, making it a destination for groups, celebrations and film fans wishing to watch the glitterati from above the crowds.

As part of the promotion, customers who book axe throwing (which Momoa has said he enjoys!) for groups of four or more between 19^th and 25^th June will receive a complimentary Prosecco Acquerrello DOC version of the cocktail to share. Axe throwing is among the activities offered at the venue, as well as darts, shuffleboard and beer pong, which can all be enjoyed alongside the cocktail menu.

The Jason Mamosa will be available exclusively for the week of the premiere, with advance booking required. Availability is limited, and the bar has explained the cocktail will be served while supplies last. 

Food Desk

The Jason Mamosa is available from 19^th until 25^th June 2026 at Rocket Room, 2^nd Floor, Market Place Leicester Square, London WC2H 7JX. For further information or to book a table, call 020 3150 3470 or visit the bar’s website here.