Hasselbackspotatis

Ingredients

• 2¼ lbpotatoesmedium, floury or Yukon Gold; scrubbed
• 1⅔ ozbuttermelted, for brushing
• 1 tspsaltflaky sea salt preferred, plus more to finish
• ½ tspblack pepperfreshly ground
• 4thymefresh sprigs, in the butter or tucked between slices
• 3 clovesgarlicthinly sliced or finely chopped
• 3 tbspolive oilmixed with the melted butter (optional)
• 1 tbsprosemarychopped, for the herb butter (optional)
• ⅔ ozcheesee.g. Parmesan or Gruyère, grated, sprinkled on near the end (optional)
• 2 tbspbreadcrumbssprinkled on with the cheese for the last minutes (optional)

Method

1. Prepare the oven and trayHeat the oven to 200–430 °F and line a baking tray or ovenproof dish with baking paper.
2. Scrub and trim the potatoesScrub the potatoes and peel them if you like. Cut a thin slice off the bottom of each one so it sits flat and steady.
3. Slice the potatoes thinlyLay each potato between two chopsticks or in a large spoon and cut across it at 2–3 mm intervals. The chopsticks or the rim of the spoon stop the knife from cutting all the way through.
4. Make the seasoned butterMelt the butter and stir in the salt and pepper. Add olive oil and chopped rosemary if you're using them. Either add the garlic and thyme to the butter now or set them aside for later.
5. Brush the potatoes with butterSet the potatoes cut side up on the tray. Brush generously with the butter, working it in between the slices as well.
6. Bake and baste regularlyBake for about 50–60 minutes, brushing with more butter two or three times and gently easing the slices apart. Tuck any garlic slices and thyme sprigs you didn't add to the butter between the slices now.
7. Add an optional crispy toppingIf you like, scatter grated hard cheese and breadcrumbs over the potatoes for the last 10–15 minutes and let them turn golden.
8. Test, season and serveCheck with a fork that the potatoes are cooked through. Season with more salt, ideally flaky sea salt, and serve hot.

Tips and variations

For more flavour, let the melted butter infuse with garlic, rosemary and thyme beforehand. A mix of butter and olive oil works in place of butter alone. Another version pushes pieces of cheese into the cuts, bakes the potatoes with wedges of red onion and finishes them with parsley. Bay leaves tucked into the slits add their scent during baking; remove them before serving. Small new potatoes seasoned with paprika work too. A slower version braises rather than roasts: set the potatoes in a flameproof dish with butter and water reaching halfway up their sides, push garlic into the slits, bring to the boil on the hob and then let them cook in the oven for 1.5 hours. Whichever version you make, bring the potatoes straight from the oven to the table with a few flakes of sea salt on top.