Put all ingredients in a small pan and cook it for about 15-20 minutes, or until it reduces to a thick, gravy-like sauce. Add honey gradually - you don’t want the sauce to become too sweet. Let it cool. Transfer most of it to a jar, through a sieve, keeping back half a cupful. Reduce the remains in the pan even further, adding more honey, until you get a sticky glaze.
Score the skin of the duck breast with a sharp knife, making sure that the meat is not damaged underneath. Rub with salt and pepper.
Heat a heavy based frying pan and fry the duck breasts, skin-side down for about 3-4 minutes until the skin is golden and crispy, then turn them over.
While frying the other side, brush the skin side with the glaze. Turn them over again and fry for about a minute and brush the meat side too with the glaze.
Keep turning them for a couple of minutes to make sure they don't burn, then pour over the sauce you put aside and cook for a couple of minutes or so, depending on how well-done you like your duck.
Transfer them to a plate and rest under cover. Reheat the sauce and reduce it further if needed.
Slice the duck breast into 1 cm thick pieces, the serve with the prune sauce and side dishes of your choice.