In a small bowl, whisk together mustard, and honey. Strip two sprigs of fresh thyme, and mince the leaves. Mix them into the honey mustard mixture. Set aside.
Preheat the oven to 325 degrees. Place the thinly sliced apple between the ham slices around the ham. Tuck in sliced garlic, and 3 sprigs of rosemary and three of thyme as well. Cover the ham with foil. Bake for approximately 2 hours, or until it is browned and heated through to at least 145 degrees. Uncover the ham and baste the honey mustard glaze over the top of the ham during the last 45 minutes.
Remove the ham from the pan and place it onto a serving dish. Remove the cooked sprigs of rosemary and thyme and replace them with fresh sprigs – they will look prettier. Spoon some of the drippings from the baking pan over the ham. Serve with additional apples for decoration, if desired.