Preheat oven to 400°F (200°C). Spray a 9x13-inch dish with nonstick cooking spray.
In the prepared dish, spread a thin layer of Alfredo sauce (about ½ cup).
Arrange half of the frozen ravioli in a single layer over the sauce. Keep them flat and even so everything cooks at the same rate.
Add half of the chicken on top of the ravioli.
Spread about half of the remaining Alfredo sauce on top of the chicken and ravioli.
Repeat the layers once more using the remaining ravioli, chicken, and sauce, in that order.
Cover tightly with aluminum foil, pressing the edges to seal. Bake for 30 minutes.
Remove the foil, sprinkle the peas over top (if using), and finish with the shredded cheese.
Return the dish to the oven uncovered for 10 more minutes, or until the cheese melts and the ravioli is tender. For browned cheese, place the dish under the broiler for a minute or two, watching closely so it does not burn.
Let the dish rest for 5 to 10 minutes before serving. Garnish with fresh herbs if desired.