Oven-baked Easy Chicken Cordon Bleu Casserole has all of the flavor and crispiness of the classic dish but none of the mess. It's quick and easy to prepare and, best of all, it can be made ahead.
Spray a 9x13-inch baking dish with non-stick cooking spray or grease with butter. Set aside.
Cut the breasts evenly in half length-wise to make six cutlets about a half-inch thick.
Place the cutlets in the baking dish and season both sides with salt and pepper.
Place a double slice of ham (or two thinner slices) to cover each cutlet.
Top each cutlet with a slice of Swiss cheese. Make sure the cutlet is covered with the ham and cheese.
Add the melted butter to the panko bread crumbs and mix to combine. Sprinkle the panko mixture evenly over the cutlets and bake for 25 minutes or until the meat is done and registers 165 °F on a meat thermometer.
Sauce Directions :
While the casserole bakes, make the sauce by adding the butter to a large saucepan over medium heat.
When the butter has melted, add the flour and constantly stir for about two minutes.
Slowly add the milk and constantly whisk to avoid lumps. Add the bouillon base and continue whisking until it thickens, which should take about four minutes.
When the sauce is bubbly and thickened remove it from the heat and stir in the mustard, Worcestershire sauce, and cheese. Stir until the sauce is smooth and creamy.
Keep the sauce warm until the casserole is ready to serve. If it becomes too thick, add a tablespoon or more of milk and stir until it is the right consistency.
Before serving, top each cutlet with the sauce, and enjoy!
Notes
To ensure your chicken cooks evenly, your cutlets should be roughly the same size and thickness. If they are not, use the smooth side of a meat mallet or rolling pin to pound them until they are even.If your cutlets are thicker or thinner than a half-inch, the meat will take more or less time to cook. I suggest checking the chicken at 20 minutes to ensure you don't overcook it. Allow the casserole to rest for a few minutes before serving. This will help the juices to redistribute in the chicken.To make this casserole ahead, prepare the cutlets and top them with the ham and Swiss cheese. Cover with plastic wrap. Mix the panko and butter and store them separately. Make the sauce, cool and store separately. Store everything in the refrigerator for up to 24 hours. Then, take the casserole and sauce out of the fridge and allow them to come to room temperature for about an hour before baking. Top the cutlets with the panko mixture and bake as directed. While the casserole bakes, place the sauce in a saucepan over low heat and gradually heat it. Stir frequently to keep it from scorching. You may need to add a little milk to thin it.