To assemble quesadillas, place tortilla on griddle or in a pan. Evenly layer with 1/4 cup cheese, 1/3 cup corned beef, 1/3 cup slaw mixture and additional 1/4 cup cheese; top with a second tortilla. Place griddle or pan over medium heat. Grill quesadillas untul golden brown on both sides and cheese is melted, turning once. Repeat with remaining tortillas, cheese, meat, and slaw mixture. Cut into wedges to serve. Serve with additional dressing if desired.