In a hot sauté pan, sear the andouille for 1 minute on each side. Remove the sausage from the pan. Stir in the flour and oil and cook, stirring constantly, until a brown roux is formed, about 2 minutes.

Add the onions, peppers, and garlic and cook, stirring, until the vegetables begin to wilt, 2 to 3 minutes.

Return the andouille to the pan and stir in the veal reduction and Creole mustard. Bring the liquid up to a boil, then reduce the heat to a simmer and cook for 15 minutes, or until the vegetables are wilted and the sauce is like a gravy. Season with salt and pepper to taste.

Divide the smothered andouille between the two split loaves. Mound each sandwich with the slaw . Serve with Zapps.