PIMMS
James Pimm was the son of tenant farmers who created the gin-based cocktail known as Pimm's. He opened his first oyster bar in 1823 and within 10 years, was running a chain of five restaurants patronised by city gents from the Bank of England, Lloyds of London and the Stock Exchange.
Pimm devised the cocktail to accompany the shellfish and the recipe was a closely guarded secret then and remains so to this day — known only to six people in the company.