Corned beef and cabbage shepherd's pie

Put the corned beef in a pot with onions, celery and its spice packet; cover with cold water, no salt.

Bring to a boil over high heat; skimming is optional. Drop to low, cover and simmer gently three and a half hours.

Lift the beef out to a bowl and let it cool fully before cutting.

Taste the broth for salt and add some if needed; bring back to a boil over medium-high.

Core the cabbage, cut into about two-inch pieces, and boil five minutes until just softening; remove to a bowl to cool.

Boil the thickly sliced carrots about five minutes until just softening; remove to cool.

Reduce to medium and boil the potatoes in the same liquid until tender enough to mash. Keep the liquid.

Separate the beef at the fatty seam, trim any large solid fat, and slice across the grain.

Mash the potatoes with butter, salt, black pepper, cayenne and milk until smooth, starting slowly so the milk does not splash; stir in grated cheddar.

In a buttered casserole dish, layer the cabbage pressed firmly, then the carrots pressed down, then an even layer of corned beef, mixing fatty and lean pieces.

Pour over one cup of the corned beef broth.

Dollop the mashed potatoes over, spread to the edges with a spatula, and texture the top with a fork in both directions; sprinkle more grated cheddar on top.

Bake in the center of a 400F oven 45 minutes to an hour until browned and piping hot.

Rest about 10 minutes before cutting.

Serve topped with spring onions and some of the cooking liquid.