Hamburger Union, the fast-casual concept led by Hugh Fowler, has reportedly appointed advisors following an approach for the business. The Times this morning suggests that Coffer Corporate Leisure, led by Mark Sheehan, has been recruited following an approach from a mystery suitor. The business, which has six locations and has just announced an international franchise deals in the Gulf and Turkey, is expected to fetch about £10m. Hamburger Union is also set to open its first UK site outside of London, in Derby. It is thought that the group will appeal to trade players interested in the premium burger market and private equity.