Place an ovenproof non-stick frying pan over medium-low heat. Season the duck breasts with salt and freshly ground black pepper, and place in the pan, skin side down. Cook for 6-8 minutes, until most of the fat has rendered and the skin is crisp. Turn and cook the other side for 1 minute.
Transfer the frying pan to the oven and cook the duck for 6 minutes on medium, or until done to your liking. Set the duck aside to rest for a few minutes, then thinly slice it.
Combine the watercress, radicchio, apple, spring onions and duck sliced in a bowl.
Whisk the oil and vinegar in a small bowl. Season with salt and freshly ground black pepper.
Pour the dressing over the salad, gently toss together and serve immediately.
Variation: Replace the duck with a boneless, skinless chicken breast, or use a cooked Peking duck breast from the supermarket. You could also use slice of left-over cooked turkey. Instead of apple slices, use orange segments.
Per serving: 281 calories, 26 g protein, 14 g fat (2 g saturated fat), 10 g carbohydrate (9 g sugars), 2 g fibre, 85 mg sodium