Season the turkey breast with salt and pepper. Peel the onion and chop it roughly. Heat the oil and butter in a roasting pan and fry the turkey breast on both sides.
Add the onion cubes, stew briefly and pour in some water. Cook the meat in a closed saucepan over medium heat for approx. 35 minutes.
Remove the turkey breast and keep warm.
Puree the roast set, pour in the red wine and bring to the boil once.
Quarter the prunes, add and heat for approx. 5 minutes.
Season the sauce with salt, pepper and cinnamon and, if desired, thicken with a little flour.
Cut turkey breast into slices, arrange on plates with the sauce and pom poms and serve.