Here are the ingredients you’ll need to create this comforting and flavorful Creamy Chicken and Pea Casserole. We’ve kept it simple and focused on fresh, quality ingredients to ensure the best taste and texture.

• Chicken Breast: (1.5 lbs) Boneless, skinless chicken breasts are the star protein of this dish. They provide a lean and satisfying base. You can also use chicken thighs for a richer flavor, but breasts are generally preferred for their ease of preparation and leaner profile in a casserole. Ensure they are cut into bite-sized pieces for even cooking and easy eating within the casserole.
• Frozen Peas: (1 cup) Frozen peas bring a burst of sweetness and vibrant green color to the casserole. They are convenient and readily available, making this recipe easy to whip up any time. No need to thaw them beforehand; they’ll cook perfectly in the oven. Peas also add a lovely textural contrast to the creamy sauce and tender chicken.
• Cream of Chicken Soup: (2 cans, 10.5 oz each) This is the creamy backbone of our casserole sauce. Cream of chicken soup provides richness, body, and that classic casserole flavor we all know and love. Look for reduced-sodium options to control the salt content of your dish. It acts as a binder and a flavor enhancer, creating that signature creamy texture.
• Milk: (1/2 cup) Milk thins out the cream of chicken soup to create the perfect creamy consistency. It ensures the sauce isn’t too thick and coats all the ingredients evenly. You can use whole milk for extra richness, or 2% or skim milk for a slightly lighter option without significantly impacting the texture.
• Shredded Cheddar Cheese: (1 cup) Cheddar cheese adds a sharp, savory flavor and a beautiful golden-brown topping to the casserole. It melts beautifully, creating a cheesy, gooey layer that’s irresistible. You can use mild, medium, or sharp cheddar depending on your preference for cheese intensity. Pre-shredded cheese is convenient, but shredding your own from a block will melt more smoothly and often have a fresher flavor.
• Onion: (1 medium) A diced onion provides a foundational savory flavor base. It’s sautéed before being added to the casserole to soften it and mellow its sharpness, contributing a subtle sweetness and aromatic depth to the overall dish. Yellow or white onions work well, offering a mild, versatile flavor.
• Garlic: (2 cloves) Minced garlic adds a pungent, aromatic kick that enhances the savory notes of the casserole. Freshly minced garlic is recommended for the best flavor, but pre-minced garlic from a jar can be used for convenience. Garlic is a key flavor component that complements the chicken, peas, and creamy sauce.
• Butter: (2 tablespoons) Butter is used to sauté the onion and garlic, adding richness and flavor right from the start. It helps to soften the onion and garlic and create a flavorful base for the casserole. Butter also contributes to the overall richness and mouthfeel of the dish. You can use salted or unsalted butter; if using salted, you may want to adjust the added salt later in the recipe.
• All-Purpose Flour: (2 tablespoons) Flour acts as a thickening agent for the sauce. It helps to create a slightly thicker and more cohesive sauce when combined with the butter and milk. This ensures the sauce coats the ingredients nicely and doesn’t become too thin or watery during baking.
• Dried Thyme: (1 teaspoon) Dried thyme adds a subtle, earthy, and slightly minty flavor that complements the chicken and creamy sauce beautifully. It’s a classic herb that enhances the savory profile of the casserole. Dried thyme is convenient and readily available, but fresh thyme can also be used (about 1 tablespoon chopped fresh thyme).
• Salt and Black Pepper: (To taste) Salt and black pepper are essential seasonings to enhance all the flavors in the casserole. Seasoning properly at each stage is crucial for a well-balanced and flavorful dish. Adjust the amount of salt and pepper to your personal preference. Taste the sauce before baking and adjust seasoning as needed.
• Bread Crumbs (Optional): (1/2 cup) Bread crumbs, especially panko bread crumbs, add a delightful crispy topping to the casserole. They provide textural contrast and a golden-brown crust. If you prefer a softer topping, you can omit the bread crumbs. Tossing the bread crumbs with a little melted butter before sprinkling them on top will enhance their flavor and crispness.