Inspiring vegetarian recipes
Try our vibrant veggie dishes, from meat-free lasagne to vegetable curry and vegetarian chilli
Heat the oven to 160C/fan 140C/gas 3. Line a 20cm square tin with baking paper.
Peel the potatoes, then carefully slice them as thinly as possible on a mandoline. Tip into a bowl. Melt the duck fat in a small pan over a low heat and pour over the potato slices. Season well with 1 tbsp of salt, and some black pepper. Toss well so that each slice is coated.
Layer the potatoes, overlapping, in the tin, working in layers until all the potatoes are used up. Drizzle over any remaining fat in the bowl. Cover with foil, sealing tightly, and cook in the oven for 1 hour 30 minutes-2 hours or until a knife inserted into the middle goes through without resistance.
Leave the potatoes to cool, uncovered, then cover with a sheet of baking paper. Put a chopping board, plate or small tray on top of the potatoes, pressing down, adding a few heavy tins or weights (a pan filled with water works well) to maintain the pressure. Transfer to the fridge and chill overnight.
About an hour before you’re ready to cook, transfer the potatoes to the freezer to firm up more. Fill a heavy-based pan no more than half full with the oil and heat to 180C or until a cube of bread browns in 30 seconds.
Lift the potato block from the tin using the paper, and cut into squares or chunky rectangles for thick chips. Carefully lower the potatoes into the oil in small batches using a slotted spoon. Leave them undisturbed to prevent them from breaking up. Cook for 4-5 minutes until golden brown and crisp. Drain on kitchen paper while you fry the rest.
Season with more sea salt, and serve with a dip of your choice (see below), if you like.