Simone Caporale, of the Artesian bar at the Langham Hotel has won the 'Bloom Signature Serve Cocktail Competition'.
Caporale came top with his creation, the Lavender Daisy, which won him a £250 cash prize, plus a further £250 for the bar.
Ten London's bars went head-to-head in at the grand final held in Searcy's, on November 23.
The final cocktails were judged by Bloom creator and master distiller, Joanne Moore, Bar Magazine editor, Mark Ludmon and bar manager at Graphic Bar, Sarah Mitchell.
Moore, said: "Overall the quality of the 10 finalist cocktails was very high which made the choice quite difficult. I was very impressed by the effort each entry had made to connect with the aroma and profile of Bloom.
Other contestants included bartenders from; The Ritz, The Hilton Berry Bar, Chelsea Brasserie, Hotel Verta, Detroit Bar, Searcy's Barbican and Coq D'Argent.