Preheat oven at 350°F. In an ovenproof skillet heat a shadow of oil on high heat. Score the duck breasts skin lightly with a knife making sure that it is not pierced all the way through. Generously salt and pepper both sides of the duck breast.
When the skillet is hot, add the duck skin side down. Cook until the skin is golden brown, about 5 minutes, turn to the other side and cook for 3 minutes. Turn again, skin side up, discard all of the fat from the pan and place in the hot oven. Cook for another 10 to 15 minutes.
Remove from the oven and cover with aluminum foil to keep warm.
Remove all the fat rendered from the duck breast, remove any large burn bits, if any in the skillet. Return the skillet to medium heat and add the cranberries and heavy cream. Lower the heat to see just a light simmer of the cream. Cook until thickened, 5 minutes.
Add the raspberry jam to the cream-cranberries sauce and blend well.
Spread the sauce on the bottom of the plate and serve the duck sliced over it.