Parsnip salad with preserved lemon and watercress

Ingredients

• 1kg parsnips, peeled and quartered lengthways
• 75ml olive oil
• 2 preserved lemons, halved, seeds discarded, skin and flesh finely chopped (40g)
• 30g blanched hazelnuts, toasted and roughly chopped
• 1 tbsp lemon juice
• 1 tbsp runny honey (or maple syrup)
• 1 tsp dijon mustard
• 80g watercress (or rocket)
• 20g parmesan, finely grated
• Fine sea salt and black pepper