When she was seventeen, she began A Taste of Honey as a novel but realised that it would be better as a play. The reason she gives for changing from the novel to drama is interesting; she objected that 'North County people are shown as gormless, whereas in actual fact they are very alive and cynical' (quoted from an interview with Laurence Kitchen, 1959). She saw a production of a play entitled Variations on a Theme by Terence Rattigan, which she considered bland and trivial, and was convinced that she could do better. So she took a fortnight off work to adapt her novel into a play.

In 1958, A Taste of Honey was accepted by Joan Littlewood, a famous director, who strongly believed that plays should be about ordinary people, not genteel middle-classes portrayed by writers like Rattigan. It opened in the East End of London in May 1958, transferring to the West End early the following year, where it enjoyed a long run and won several awards. The critic and film director Lindsay Anderson called it 'A work of complete, exhilarating originality.' In 1960 A Taste of Honey was staged in New York and won a drama prize. Two years later Shelagh wrote the screenplay for the film version, which won an Academy Award. At the age of 23, she had become one of the most famous writers of her time.