Preheat the grill to full whack. Place the whole peaches onto a snug-fitting baking tray and pop under the grill for 8 to 10 minutes, or until soft and blackened on top, then leave aside to cool.
Once cool, peel the skin off the peach, then halve, discard the stone and tear the flesh into rough 2cm chunks.
Arrange the Parma ham on plates, crumble over the cheese and scatter the peach chunks and radicchio on top. In a small bowl, mix 2 tablespoons balsamic with 4 tablespoons extra virgin olive oil and drizzle over the salad. Season lightly with salt and pepper, before serving.