Ingredient

Cottage pie

Cottage pie is minced beef in gravy under a lid of mashed potato. Shepherd's pie is the same dish with lamb. The distinction is real and modern — for much of the nineteenth century both names were used loosely — and it is worth keeping because the two meats want slightly different treatment.

The two things that go wrong

A watery filling and a pale, soggy top. Almost every disappointing cottage pie is one or both, and both have straightforward causes.

The filling is watery because the mince was not browned and the liquid was not reduced. Mince tipped into a pan in one lump releases its water, sits in it and greys. Browning mince properly means a hot pan, not too much at once, and leaving it alone long enough to catch before breaking it up. It should be genuinely brown in places, not uniformly beige.

Then the gravy has to be reduced until it is thick, before the potato goes on. A filling that looks slightly too dry in the pan is about right, because it will loosen in the oven; one that looks correct in the pan will be soup under the mash.

The top is pale because the mash was too wet, or because there was nothing on it to brown. Mash for a pie wants to be stiffer than mash for eating — floury potatoes, well steam-dried, with butter and only a little milk. Fork the surface into ridges, because ridges brown and a flat surface does not, and finish with butter or grated cheese.

The method

1. Brown the mince hard in batches in a wide pan. Do not stir it constantly; let it catch. Lift it out.
2. Soften finely chopped onion, carrot and celery in the fat, slowly, until sweet.
3. Add tomato purée and cook it out for a minute, then a spoonful of flour.
4. Return the mince, add stock, Worcestershire sauce, bay and thyme, and simmer.
5. Reduce it until thick — thicker than seems right. Twenty to forty minutes. Taste and season properly.
6. Meanwhile boil floury potatoes until completely tender, drain, and let them steam dry in the pan for a few minutes.
7. Mash with butter, a little warm milk, salt and pepper. Keep it stiff.
8. Cool the filling slightly before topping it. Hot filling makes the mash sink into it.
9. Spoon the mash on in blobs and spread from the edges inwards, so it seals to the sides of the dish and the filling cannot bubble up round it.
10. Fork the surface into ridges, dot with butter or scatter cheese, and bake until bubbling at the edges and properly browned on top.

The variations

Cottage pie

Beef. The word "cottage" is older and referred to any meat under potato.

Shepherd's pie

Lamb — shepherds keep sheep. Usually cooked with rosemary rather than thyme, and it wants a little more acidity to cut the fat.

Cumberland pie

The same with a breadcrumb or breadcrumb-and-cheese topping over the mash, for extra crunch.

Fish pie

A different dish sharing the mash lid — white sauce rather than gravy, and much shorter cooking.

Additions worth making

Mushrooms fried separately, a splash of red wine, a spoonful of Marmite or soy for savouriness, grated cheese in the mash.

Made with leftovers

The original point of it — cooked meat from a joint, minced or chopped, in gravy. Much quicker, and it needs less cooking.

What goes wrong

• Watery filling. Not browned, not reduced. Reduce further than feels right.
• Pale top. Wet mash, a flat surface, or an oven that was not hot enough. Fork it into ridges and add butter or cheese.
• Mash sinking into the filling. The filling was too hot or too loose. Cool it and thicken it.
• Gluey mash. Over-worked, or a waxy potato. Use floury potatoes and a ricer or a masher, never a food processor.
• Bland. Under-seasoned, and no savoury backbone. Worcestershire sauce, a little soy or Marmite, and proper salt.
• Filling bubbling over the sides. The mash was not sealed to the edge of the dish.

Common questions