butter to grease
1kg/2¼lb potatoes, peeled
1 tbsp fresh thyme leaves
475ml/16fl oz/scant 2 cups hot vegetable stock
salt and ground black pepper
1 Preheat the oven to 200°C/400°F/Gas 6. Butter a large ovenproof dish.
2 Slice the potatoes very thinly, preferably with a mandolin. Arrange half the slices in a layer in the buttered dish. Sprinkle with some of the thyme and salt and pepper and cover with the rest of
3 Pour the hot stock over the top and place a sheet of buttered parchment paper on top of the potatoes.
4 Cook in the oven for 30 minutes, then remove the parchment paper and cook uncovered for 1 hour until the potatoes are cooked and crisp and golden brown on top. Serve hot.