For the sauce, in a bowl, combine mayonnaise with sauce mix, ketchup, and relish. Thin with a little warm water so sauce is runny—you should be able to drizzle easily. Set aside.
In a Multipurpose or Round Steamer, combine meat and seasoning. Cover; microwave on high, 3–5 min or until cooked through. Use Ground Meat Separator to break up large chunks. Drain any excess liquid.
Meanwhile, cut tomatoes into halves.
To assemble, place tortillas on plates. Spoon meat overtop and sprinkle with tomatoes, coleslaw, and cheese, then drizzle on sauce. Add toppings, if desired.