Winter apple and walnut salad

Ingredients

• 70g salad leaves such as rocket or watercress
• 5 red and white chicory, washed and leaves separated
• 1 red apple, cored and thinly sliced
• 75g walnut halves, roughly chopped
• 3 tbsp olive oil
• 1 tbsp cider vinegar or red wine vinegar
• 2 tsp wholegrain mustard
• 50g Parmesan shavings