Directions
In a small bowl, stir together mayonnaise, ketchup, and sweet pickle relish. In a separate medium bowl, mix together cabbage, apple cider vinegar, and light brown sugar. Spread the mayo/ketchup mixture on 4 slices of bread. Place slices of corned beef (2 ounces each sandwich) and Swiss cheese (1 slice per sandwich) on top. Spoon the cabbage mixture over the cheese and cover with the remaining slices of bread. Lightly spray outer surfaces of bread with vegetable oil spray. Cook on a flat griddle, grill over medium heat, or use an electric panini maker, until sandwiches are browned and cheese is melted.