Bake puff pastry according to package instructions.
While puff pastry is baking, combine gravy, lemon juice, chicken, broccoli, ½ cup of the cheese, and seasoning in a large saucepan. Cook over medium heat, stirring frequently, until heated through.
Serve in pastry shells with remaining cheese sprinkled on top.
Notes
Nutrition calculation uses 1 teaspoon Montreal Chicken Seasoning.
Servings are calculated using 1 puff pastry per serving.