• 1 litre (35 fl oz/4 cups) vegetable oil, for deep-frying
• 900 g (2 lb) boiling potatoes, peeled, halved and each half quartered
• ½ teaspoon fine sea salt
• 3 tablespoons olive oil
• 1 large onion, finely chopped
• 60 g (2¼ oz) piquillo peppers, or other roasted red capsicums (peppers), chopped
• 2 garlic cloves, finely chopped
• 600 ml (12 fl oz) tomato passata (puréed tomatoes)
• 1 large pinch caster (superfine) sugar
• 1 tablespoon sweet smoked paprika
• ½ teaspoon cayenne pepper
• 1 bay leaf
• sea salt flakes
• freshly ground black pepper

Heat the vegetable oil in a large pan. Sprinkle the potatoes with salt and very gently simmer in the oil for 15 minutes until tender but not coloured. Drain and reserve the oil.

Heat the olive oil in a pan and gently fry the onion and peppers or capsicums over a low heat for 10 minutes until soft and sweet. Add the garlic and cook for 5 minutes more. Add the tomato passata, sugar, paprika, cayenne and bay leaf and simmer to a thick sauce. Season well with salt and pepper, remove the bay leaf and set aside.

Reheat the reserved oil until very hot and quickly fry the potatoes until golden. Remove from the oil with a slotted spoon. Serve immediately, with the sauce spooned over.