Method
Put the pine nuts into a small pan and toast over a medium heat for 3-5 minutes until golden, shaking the pan regularly to prevent burning, then tip the nuts into a saucer and set aside. Put the olive oil, vinegar, mustard and honey into a large mixing bowl, together with a generous pinch of salt, and whisk to combine. Add the red onion slices and toss to coat well in the dressing, then set aside for at least 10 minutes. Next, line a tray with kitchen paper. Place a frying pan over a medium heat, and when hot, add the pancetta slices (you will probably need to cook them in batches). Cook the slices for 2-3 minutes per side, until sizzling and lightly golden, then lift them on to the paper-lined tray to drain. Shred the prepared sprouts as finely as you can – this is easiest in a food processor – then add them to the onion bowl. Use a potato peeler to shave the cheese into the bowl, then mix everything together gently. Transfer the dressed sprouts, onions and cheese to a serving dish, then crumble over the pancetta, scatter over the toasted nuts and serve.