Ottolenghi’s potato salad

Method

1. Put the potatoes in a medium saucepan (one with a lid). Add just enough water to cover, salt generously and set over a medium-high heat. Bring to the boil, then reduce the heat to low-medium and cook, covered, for 20-25 minutes until just tender. Drain and, once cool enough to handle, remove the skins, then slice into 0.5cm-thick rounds. Set aside in a medium bowl.
2. Pour 2 tbsp of the oil into a medium sauté pan or deep frying pan and set over a medium heat. Add the onion and cook for 12-15 minutes, stirring regularly, until caramelised. Add the garlic and stock, bring to a simmer, then remove from the heat. Add the mustard, vinegar, salt, black pepper and another 2 tbsp oil. Whisk to combine, then pour the mixture over the potatoes. Mix gently but thoroughly: it will look wet (and some of the potatoes will break up), but this is normal.
3. Set aside for about 2 hours, for the potatoes to soak up about half the broth, then stir in the finely chopped chives.
4. Meanwhile, wipe the sauté/ frying pan and set over a medium-high heat. Add the pancetta, reduce the heat to low-medium and cook for 10-12 minutes, stirring occasionally, until crisp. Using a slotted spoon, transfer to a plate lined with kitchen paper – leave about 1 tbsp of the fat in the pan – and set aside. Once cool, finely chop the pancetta.
5. Add the remaining tbsp of oil to the fat in the pan, along with the paprika. Stir for 30 seconds or so until fragrant, then remove from the heat. When ready to serve, fold the cucumber into the potato salad and transfer to a serving plate. Scatter over the pancetta crumbs, along with the longer chive lengths. Spoon over the paprika oil and serve.