The agency won the business in a final shoot out against 18 Feet & Rising. The incumbent, Saatchi & Saatchi New York, and other pitching agencies Fred & Farid Paris and The Collaborators were knocked out at an earlier stage.
BBH has been briefed to produce the first global campaign for Old El Paso, which will run primarily in Europe and Australia.
Isabelle Moynier, the international marketing director at Old El Paso, said: "We are delighted to embark on this new collaboration with BBH. Old El Paso is a unique brand that brings fun and smiles to the table from Canada to Australia.
"There is still enormous untapped potential of penetration headspace and BBH will be a great partner to rally around Old El Paso all the people looking for a spark in their meals."
Ben Fennell, the chief executive of BBH, said: "If you can't have fun working on a brand like Old El Paso, then you are working in the wrong industry. It's a great brand, with great clients, and it deserves great work."
In May, the Mexican food brand launched a one-off outdoor and digital campaign, created by Work Club, to coincide with the Jubilee weekend.
UK media planning and buying for Old El Paso will continue to be handled by UM London, General Mills' media agency.