Hot dressed sweet potato, fennel & feta parcels

INGREDIENTS

• 1 sweet potato , peeled and cut into wedges
• ½ small fennel bulb , sliced
• 1 tbsp orange juice , plus a grating of zest
• 1 tbsp olive oil
• 2 tsp red wine vinegar
• 1 tsp runny honey
• 1 tbsp chopped flat-leaf parsley
• 1 tbsp walnuts , roughly chopped
• 50g feta cheese , crumbled (or any salty, soft vegetarian cheese)