Place apples, water, sugar and cinnamon in saucepan over medium heat. Cook, sitting occasionally, until liquid is absorbed and mixture is dark brown and thickened (about 30 minutes). Allow to cool. Spread softened butter on one slice of bread, top with two slices of Swiss cheese, spread apple mixture over cheese. Butter second slice of bread, top with cheese and put on top. In sauté pan cook sandwich on low heat, being careful not to burn the bread and giving the cheese time to soften. Flip the sandwich and brown the other side until golden.