Lancashire Hotpot | British Lamb Bake with a Sliced Potato Topping

Season the lamb slices with salt and black pepper. Heat the oil well in a wide skillet and brown the meat in two batches, until deeply browned on all sides, for 8–10 minutes total. Transfer it to a deep baking dish.

In the same skillet, cook the thick half-moon onion slices for 8 minutes, until softened. Sprinkle in the flour and cook for 1 minute. Add the stock and bring to a boil, scraping up the browned bits from the bottom of the pan with a spoon.

Peel the potatoes and slice them 3 mm thick. Do not rinse the slices; their starch helps the topping hold together.

Pour the onions and gravy over the lamb, then tuck in the thyme and bay leaf. Arrange the potato slices from the edge toward the center, overlapping each slice by half like fish scales; use at least two layers. Brush half the melted butter over the surface and sprinkle with salt.

Cover the dish with its lid or seal it tightly with foil. Bake in a preheated 160°C / 320°F oven for 2 hours. A fork inserted at the edge should slide into the meat without resistance.

Remove the lid, brush the remaining butter over the potatoes, and raise the oven temperature to 200°C / 390°F. Bake for 30 minutes more, until the top potatoes are golden brown with crisp edges.

Let the hotpot rest, then serve it with a deep spoon so each portion includes both the crisp top and the meat. Pickled red cabbage is a traditional accompaniment.