Preheat the oven to 425°F

Peel the potatoes and place in a bowl of cold water to prevent browning.

Place a potato in a large wooden spoon. Using a sharp knife make slices widthways across the potato about 5 mm (¼”) apart (some people making them even closer), making sure to cut down to the lip of the spoon but not all way through the potato. Return the potato to the bowl of water. Repeat with the remaining potatoes.

Brush the bottom of a shallow roasting tray with the melted butter.

Dry the potatoes and place them cut side up in a roasting tin. Drizzle with half of the butter then season with salt and pepper.

Bake for 25 minutes. Remove from the oven and drizzle with the remaining butter. Sprinkle with breadcrumbs and season with a little more salt. Return to the oven and bake for another 25 to 35 minutes, or until nicely browned. (They may need basting with the melted butter a couple more times.)

Serve with sour cream, crispy bacon, chopped chives