Preheat oven to 180°C.
Season turkey breast with Vegeta Gourmet stock powder, black pepper and rosemary.
Pour olive oil in the baking dish and place in the turkey, onions and apples.
In a bowl mix apple juice, apple veniger and mustard and pour over the turkey.
Cover with aluminum foil and bake for 1 hour.
Uncover and pour the juices over meat and bake for another 20 minutes.