1.
Melt the butter and add in the oil, the zest and juice of the two oranges, the finely chopped garlic, and the salt and pepper. Spread this sauce all over the turkey, both on top of the skin and underneath, lifting it carefully so that it does not tear.
2.
Preheat the oven to 428 F. Set the turkey in a baking dish and put it in the oven. Turn the temperature down to 356 F and bake for about four hours. Throughout the cooking process, baste the turkey with its juices every half hour or so to make sure it does not dry out.
3.
While the turkey is in the oven, prepare the sauce. Heat the
olive oil together with the
balsamic vinegar in a small pot. Let the mixture come to a boil and then remove it from the heat. Add the mustard, honey and salt and pepper to taste.
4.
Serve the turkey with a bowl of the warm sauce on the side, so that everyone can serve themselves to their liking.