Grate the cheese, or cut it in thin slices. Put the ale in a clean saucepan, make it hot; then put in the cheese, next the butter and mustard. Have the slices of hot buttered toast neatly trimmed and ready on a hot dish. Stir the cheese mixture continuously over a gentle heat until it has become thick, smooth, and creamy, then immediately pour it over the toast, and serve it as quickly as possible, or it becomes tough.
N.B. - The quality of the cheese makes all the difference to the dish. It should be mild and rich.
The quantity of the ale required will vary according to the staleness of the cheese. If preferred, use cream or milk in place of ale.