Place cabbage in water with a teaspoon of salt & black pepper each. Add 1 tablespoon of sugar and one cup of prepared chicken broth. Bring to a boil, reduce heat to a simmer and cook until cabbage is fork tender. Drain and set aside
Peel potatoes and cut potatoes, placing in water with 1 tablespoon salt. Boil potatoes until they are cooked through. Drain and place potatoes with cooked cabbage. Using a potato masher lightly blend potato and cabbage until incorporated.
Add the chopped corned beef and scallions mix. Add Kosher Salt and black pepper. Place mix in refrigerator for about an hour or until cool enough to handle by hand.
Place wonton on flat surface with one slice of cheese (about a half ounce) and place about 1 - 2 ounces of your potato and cabbage mixture on top of the cheese in the wonton. Roll the wonton away from you, about half way tuck the left and right ends of the wonton into the roll. Continue rolling until you have a round egg roll shape. Take a little dab of water an coat the wonton to seal.
Place wontons in vegetable oil at 350 degrees for 4-5 minutes or until crispy. Let Wontons drain on paper towel. then Slice on a bias and serve with Blarney Stone Ground Mustard.