Shepherd's pie is an accredited health hazard in canteens, schools, hospitals.
Hachis parmentier is very different.
Still, here is the one shepherd's pie recipe that is worth essaying. It was my father's. His genes and voice apart I have not nicked much from him so am unabashed about this theft.
Leftover lamb leg or shoulder
1kg onions
Celery
Potato
Milk
Butter
Guinness
Worcester sauce
Angostura bitters
Sweat 500g sliced onions and celery - cook till soft
Mince the meat
Mix meat and onions / celery with half a pint of Guinness, Worcester sauce and Angosturas.
Reduce till getting still liquid but going on sticky
Mash potatoes with butter and milk. He liked them to be fairly stiff.
To the meat and veg add 500g sliced uncooked onions.
Place in an overproof dish and cover with mash. Dot with butter
Cook at 150, no hotter, for an hour. He used to furrow it with a fork and finish it under the grill
My father's is an entirely different dish from the various Parmentiers that I habitually cook. These are modelled on the best I've tasted - Yves Camdeborde's when he was at La Regalade in furthest Montparnasse. He is a marvellous chef. His current restaurant Le Comptoir de l'Odeon remains one of the hottest tickets in Paris. Extraordinarily, Parisians are willing to queue at lunchtime when there is no booking. When we steal, we should steal from the finest.
The potato is a purèe. Very definitely not mash. It is made with crème fraiche, a lot of butter, salt and pepper, garlic.
The purèe does not sit on top of the filling, it surrounds it. So the buttered and oiled receptacle is lined with purèe of about 3cm thickness and depth.
Here are some fillings: they are all more or less cooked and don't require long in the oven. Cook for about 30-40 minutes at 200.
Lamb's kidneys and liver. Chop small, partially cook and moisten with reduced stock before combining with the puree.
Black pudding / boudin noir. The additon of apples fried with cinammon or sweated onions is admissable, depending on the components of the sausage. The best British black pudding comes from Stornoway (Charles Macleod or Macleod and Macleod) but like Burgos morcilla the amount of grain in them makes them perhaps too dry for this dish. The best French? There are too many contenders to get into a barney about. Those which include chestnuts are worth avoiding. Those which include piment d'Espelette are to be sought. In general the softer, mousse-like texture of French boudins is more appropriate. The boudin should be cut into 2-3cm slices and mixed with the purèe.
Duck confit. Take meat off the bone. Combine with chopped prunes that have been soaked in sweet wine. Mix with purèe.
Chicken and mushroom. A nod here to chicken à la king, a fashionable dish of the late 1950s. Poach chicken breasts. Dice. Mix with button mushrooms cooked in butter. Bind with crème fraiche. Particularly good for invalids with declining dental powers.