Preheat your oven to 325°F (160°C).

In a shallow bowl, mix the flour, salt, and black pepper, then toss the lamb chunks in the mixture until evenly coated.

Heat the vegetable oil in a large oven-proof casserole dish or Dutch oven over medium-high heat.

Sear the lamb in batches until browned on all sides, about 4-5 minutes per batch, then remove the meat and set aside.

In the same pot, add the sliced onions and carrots, cooking for about 5 minutes until the onions soften and start to turn golden.

Return the browned lamb to the pot and pour in the stock and Worcestershire sauce, stirring to scrape up any browned bits from the bottom.

Add the bay leaves, then remove the pot from the heat to assemble the topping.

Arrange the sliced potatoes in neat overlapping layers over the meat mixture, starting from the outside and working your way in.

Brush the top layer of potatoes generously with the melted butter and season with a pinch of extra salt.

Cover the dish with a lid and bake in the preheated oven for 90 minutes to tenderize the meat.

Remove the lid and increase the oven temperature to 400°F (200°C).

Bake uncovered for another 30 minutes until the potatoes are cooked through and the top is crispy and golden brown.

Remove from the oven and let the hotpot rest for 10 minutes before serving hot with pickled red cabbage or crusty bread.