Creamy Chicken and Broccoli Casserole in One Pan Step-by-step instructions

Before you start

Before you begin cooking, ensure all your ingredients are prepped and measured to make the process completely seamless. Slice the chicken breasts into thin, uniform strips if not already sliced, and set them aside in the refrigerator until ready to cook to maintain food safety.

Wash the fresh broccoli thoroughly, dry it completely with a clean kitchen towel to prevent excess moisture in the casserole, and cut it into bite-sized florets. Have your seasonings, pre-made creamy sauce, and shredded cheese ready to go. Prepare a foil baking pan and preheat your broiler.

Instructions

Searing the Seasoned Chicken

1. 1Season the chicken slices
   Toss the chicken slices with the seasonings in a bowl until they are evenly coated.
   Look for The chicken slices should be completely covered in a uniform layer of seasonings.
   Tip Let the seasoned chicken sit for ten minutes at room temperature to absorb the flavors before cooking.
2. 2Sear the chicken in the skillet
   Heat a large skillet over medium-high heat. Add the seasoned chicken slices in a single layer and sear for five to six minutes, turning occasionally, until they are beautifully browned and cooked through. Ensure the internal temperature of the poultry reaches 165°F (74°C) using a digital thermometer.
   Look for The chicken should be deeply browned and register 165°F (74°C) on a thermometer.
   Safe temperature 165°F (74°C) internal temperature (poultry)
   Tip Avoid moving the chicken slices for the first two minutes to get a deep, flavorful sear.

At the end of this phase, the chicken slices should be beautifully browned and fully cooked. The kitchen will be filled with the rich, savory aroma of toasted seasonings. Check that the chicken slices have lost all pinkness and have developed a deeply caramelized, golden-brown crust on both sides before transferring them from the hot skillet. They must reach a safe internal temperature of 165°F (74°C).

Assembling with Broccoli and Cream Sauce

3. 3Arrange broccoli and chicken
   Place the fresh broccoli florets and the seared chicken slices evenly into a foil tray.
   Look for The chicken and broccoli should be evenly distributed throughout the pan.
   Tip Cut the broccoli into small, bite-sized pieces so they cook evenly with the chicken.
4. 4Drizzle with creamy sauce
   Drizzle the creamy sauce evenly over the fresh broccoli and chicken slices in the foil tray, ensuring everything is well coated.
   Look for The ingredients should be coated in a glossy layer of cream sauce.
   Tip Gently toss the ingredients in the tray to distribute the sauce into every nook and cranny.

The casserole should now be fully assembled in the foil tray, with the vibrant green broccoli florets and golden chicken slices evenly distributed throughout the pan.

The warm, seasoned cream sauce should be drizzled thoroughly over all the ingredients, pooling slightly at the bottom of the tray. The entire mixture should look moist, glossy, and ready to absorb the rich, creamy flavors during the broiling process.

Broiling the Cheese Topping

5. 5Top with cheese and broil
   Scatter the cheese evenly over the top of the casserole. Place the foil tray under the preheated broiler and broil for three to five minutes until the cheese is bubbling, molten, and beautifully speckled with golden-brown spots. Remove from the oven and let rest for five minutes before serving.
   Look for The cheese should have a deeply golden, bubbly, and slightly charred crust.
   Tip Keep a close eye on the broiler, as cheese can go from golden to burnt very quickly.

The casserole is complete when the cheese on top is completely melted, bubbling vigorously, and speckled with golden-brown spots. The edges of the dish should be bubbling with hot cream sauce, and the broccoli should look tender and vibrant. A beautiful, stretchy cheese pull should occur when scooping into the center of the warm casserole, releasing an incredibly appetizing steam.

Common mistakes

One common mistake is using frozen or pre-boiled broccoli, which releases too much water during baking and dilutes the rich cream sauce, resulting in a soggy, runny casserole. Another error is crowding the skillet when searing the chicken slices.

If the pan is too full, the chicken will steam in its own juices instead of searing, preventing the development of that flavorful golden crust. Cook the chicken in batches if necessary to ensure a proper sear. Finally, avoid using pre-shredded packaged cheese, which contains starches that prevent a smooth melt.

How to tell it’s done

To ensure the chicken is perfectly cooked, juicy, and safe to consume, use an instant-read digital meat thermometer inserted into the thickest chicken slice. The internal temperature must reach 165°F (74°C).

The broccoli should be easily pierced with a fork but still retain a slight, tender-crisp resistance and a vibrant green color. The cheese on top must be fully melted, bubbling vigorously at the edges, and beautifully browned under the broiler, creating a cohesive, golden crust.

• Poultry: 165°F (74°C) in the thickest part