Grilled swiss cheese, turkey and caramelized onion sandwich

1. Cook onions in medium skillet sprayed with cooking spray on medium-low heat 30 min. or until golden brown, stirring frequently. Remove from heat; stir in dressing.

2. Spread 1 bread slice with mustard; top with cheese piece, turkey and onions; cover with remaining cheese piece and bread slice.

3. Spread outside of sandwich with butter. Cook in skillet on medium heat 3 min. on each side or until cheese is melted and sandwich is golden brown on both sides.