In a large Dutch oven, combine the evaporated milk, hot water, and penne pasta. Bring to a boil over high heat.
Once boiling, reduce the heat to medium-high and cook for 7 minutes, stirring frequently. Do not drain.
Reduce the heat to medium and add the shredded rotisserie chicken, cream cheese, and Alfredo sauce to the pot. Continue to cook and stir for an additional 3 minutes until the cream cheese is melted and the sauce is smooth.
Remove the pot from the heat and stir in the grated Parmesan cheese until melted. Season with salt and pepper to taste.
Cover the pot and let it rest for 5 minutes to allow the flavors to meld together.
After resting, uncover the pot and stir in the frozen peas. Serve hot and enjoy this creamy and comforting Chicken Alfredo with Peas!