Step 1: Preheat Oven and Prepare Baking Dish: Preheat oven to 350F (175C). Lightly grease a 9x13 inch baking dish to prevent sticking.
Step 2: Cook Pasta: Cook pasta according to package directions until al dente. Drain well and set aside. Rinsing with cold water can help stop the cooking process and prevent sticking.
Step 3: Combine Ingredients: In a large bowl, combine the cooked pasta, shredded chicken, 1 1/2 cups of the shredded cheddar cheese, condensed cream of chicken soup, milk, melted butter, salt, and pepper. If using, add the thawed frozen mixed vegetables. Stir until all ingredients are well combined.
Step 4: Transfer to Baking Dish: Pour the mixture into the prepared baking dish, spreading it evenly.
Step 5: Add Remaining Cheese: Sprinkle the remaining 1/2 cup of shredded cheddar cheese evenly over the top of the casserole.
Step 6: Bake: Bake in the preheated oven for 25-30 minutes, or until the cheese is melted, bubbly, and lightly golden brown.
Step 7: Cool and Serve: Remove from the oven and let stand for 5-10 minutes before serving. This allows the casserole to set slightly, making it easier to slice and serve.
Optional Tips:
For a richer flavor, substitute cream of mushroom soup for cream of chicken soup.
Add a dash of garlic powder or onion powder for extra seasoning.
Use leftover rotisserie chicken to save time.
Substitute different cheeses, such as mozzarella, Monterey Jack, or a blend of cheeses, based on personal preference.