Heat a nonstick skillet or griddle over medium heat.
Spread each of 4 slices of bread with about 1 tablespoon of dressing, then top each with one-quarter of the corned beef. Top the corned beef with 1 slice of Swiss cheese then about 1/3 cup of sauerkraut. Top the sauerkraut with another slice of Swiss cheese. Spread with another 1 tablespoon of dressing. Top each sandwich with the remaining 4 slices of bread. Butter both sides of each sandwich.
Grill in the hot pan for about 3 to 5 minutes on each side, or until the bread is nicely browned and cheese is melted.
Calories per serving: 464
Fat per serving: 36.1