For the Glaze: In a saucepan, over medium heat, combine all of the ingredients, except for the cornstarch and water and whisk well. Bring the mixture to a simmer and cook for 1 minute.
In a small mixing bowl, whisk the cornstarch and water together. Add to the hot liquid and continue to cook for 1 minute. Remove from the heat and cool completely.
Preheat the oven to 450 degrees F. Season the pork with Creole seasoning. Place the pork in a large Zip-lock bag and pour in the marinade. Marinate overnight. Remove from the refrigerator and bring to room temperature. Place the pork loin on a roasting pan, reserving the marinade. Roast for 10 minutes. Reduce the heat to 400 degrees F and continue to roast for 30 to 40 minutes, or until the temperature reaches 155 degrees F on a meat thermometer, basting every 15 minutes. Remove from the oven and rest for 10 minutes before slicing. In a saucepan, over medium heat, whisk the mustard and veal reduction together. Bring to a simmer and cook for 2 minutes.
To serve, spoon the mashed root vegetables in the center of each plate. Place the cabbage around the potatoes. Slice the pork into 1/2-inch pieces. Lay a couple of the slices against the potatoes. Spoon the sauce over the pork and garnish with parsley.