The Staffordshire oatcake is a sandwich whose bread is nothing like the biscuit that shares the name. This is a soft, floppy, savoury pancake of oatmeal, flour, and yeast, cooked thin on a hot griddle, pliable rather than crisp, closer to a Breton galette than to anything baked. That pliability is the whole identity. It is made to be folded or rolled around a hot filling while still warm, which is a structural decision a slice of bread cannot make: the oatcake bends completely around its load and seals soft against itself instead of stacking between two rigid faces. In the Potteries it is breakfast and it is regional before it is anything else.
The craft is heat and the order of assembly. The oatcake is warmed through on a griddle or under a grill, then the filling goes on while the surface is still soft enough to fold without cracking; an oatcake left to cool turns leathery and splits when bent, which defeats the format. The classic load is cheese melted under the grill so it grips the oat surface, often with bacon or sausage whose rendered fat the oatcake soaks a little without going to paste, the oat structure being sturdier than white bread under grease. It carries no separate sauce because the oatcake's own faint, nutty, slightly sour flavour is part of the seasoning and a wet dressing would only steam it limp. Folded in half or rolled into a tube, it is engineered to be eaten in the hand off a hot plate rather than packed cold.
The variations stay inside the warm, folded frame. Cheese and bacon is the baseline; sausage, egg, and the full-breakfast load each push it toward a complete meal in a single fold. A double oatcake stacks two with the filling between for a heavier build. The sweet version runs golden syrup or jam and treats the same pancake as a pudding rather than a savoury. The Derbyshire oatcake is a close regional cousin with a slightly different crumb and its own loyalties. Each deserves its own article rather than being crowded in here.