Flatten chicken to 1/4-in. thickness; sprinkle with poultry seasoning. In a large skillet, cook chicken in oil over medium heat for 4-5 minutes on each side or until juices run clear; drain.
On roll bottoms, layer the bacon, chicken and cheese. Broil 4-6 in. from the heat for 1-2 minutes or until cheese is melted. Top with romaine and onion. Spread mayonnaise over cut side of roll tops; replace tops. Yield: 4 servings.