Turn oven on to 425 degrees. Let preheat, at least 10 minutes
Finely chop broccoli. -skip if using microwave bag broccoli
Pat chicken dry.
hold knife blade parallel to the board and carefully make a lengthwise cut through the center of the meat, using your free hand to steady meat.
Stop short of opposite edge of chicken so chicken remains in one piece.
Open chicken as you would a book. -Possibly pound out flat after cutting for even size.
Place broccoli in a microwave-safe bowl. Microwave until broccoli is very tender, 2-4 minutes.
Carefully remove from microwave.
Drain excess liquid from broccoli.
Add cream cheese, half the cheddar (reserve remaining for topping), and a pinch of salt and pepper to bowl with broccoli.
Stir to combine.
Evenly divide filling between chicken breasts.
Carefully fold over the chicken, keeping the filling inside.
Transfer chicken to a sprayed baking sheet and top with poultry seasoning.
Roast in hot oven until chicken reaches a minimum internal temperature of 165 degrees, 15-20 minutes.
Carefully remove from oven.
Top chicken with remaining cheddar.
Roast again in hot oven until cheese has melted, 3-5 minutes.
Carefully remove from oven. Rest, 5 minutes.
Drizzle some lemon juice over chicken