Preheat oven to 350° F. Shred or cube all of the cheese. Place all the ingredients except the cornstarch in a medium heat proof vessel. Bake until melty (30-60 minutes). Whisk now and then. Remove from oven and whisk in the cornstarch. Serve hot with slices of apples, pears and wheat or rye crisps.

Reheat as needed.