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A golden brown Chicken Cordon Bleu Casserole with melted cheese, ham, and breadcrumbs sits ready to serve.

Ultimate Chicken Cordon Bleu Casserole

This deconstructed casserole captures all the luxurious flavor and satisfying texture of the classic Chicken Cordon Bleu with the comforting ease of a one-dish bake. It features tender chicken, salty ham, and nutty Swiss cheese in a creamy, seasoned béchamel sauce, all topped with a crispy, golden panko and Parmesan crust. Engineered to avoid sogginess, it delivers the perfect bite in every serving.
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Prep Time 25 minutes
Cook Time 40 minutes
Total Time 1 hour 5 minutes
Servings: 6
Course: Main Course
Cuisine: American, French-Inspired
Calories: 550
Ingredients Equipment Method Notes

Ingredients
  

  • 2 lbs boneless, skinless chicken breasts, cut into 1-inch cubes
  • 1 tbsp olive oil
  • Salt and freshly ground black pepper to taste
  • 1 medium yellow onion, finely diced
  • 3 cloves garlic, minced
  • 3 tbsp unsalted butter
  • 1/4 cup all-purpose flour
  • 2 cups whole milk, warmed
  • 1 cup low-sodium chicken broth
  • 2 tsp Dijon mustard
  • 1/2 tsp smoked paprika
  • 1/4 tsp ground nutmeg
  • 8 oz thick-cut deli ham like Black Forest
  • 8 oz Swiss cheese, grated divided, about 2 cups
  • 1/2 cup sour cream
  • 1/4 cup chopped fresh parsley
  • 1 1/2 cups panko breadcrumbs
  • 1/2 cup grated Parmesan cheese
  • 1 tbsp chopped fresh thyme or 1 tsp dried

Equipment

  • 9x13 inch baking dish
  • Large Skillet
  • Mixing bowls
  • Whisk
  • Cutting board
  • Chef's knife
  • Measuring cups and spoons
  • Grater
  • Spatula or wooden spoon

Method
 

  1. Preheat oven to 375°F (190°C). Lightly grease a 9x13 inch baking dish.
  2. Season chicken cubes with salt and pepper. In a large skillet, heat olive oil over medium-high heat. Cook chicken until just cooked through and lightly browned, about 6-8 minutes. Remove to a plate.
  3. In the same skillet, reduce heat to medium. Add butter and onion, cooking until soft. Add garlic and cook for 30 seconds. Sprinkle flour over the mixture and cook, stirring constantly, for 2 minutes to form a roux.
  4. Gradually whisk in the warm milk and chicken broth until smooth. Bring to a simmer, stirring, until thickened. Remove from heat and whisk in Dijon mustard, smoked paprika, nutmeg, and additional salt and pepper.
  5. In a large bowl, combine the cooked chicken, diced ham, half of the grated Swiss cheese, sour cream, and parsley. Pour the creamy sauce over and fold everything together until evenly coated.
  6. Transfer this mixture to the prepared baking dish and spread evenly. Sprinkle the remaining Swiss cheese over the top.
  7. In a medium bowl, combine panko, Parmesan, melted butter, and thyme. Mix until the breadcrumbs are evenly moistened. Sprinkle this mixture evenly over the entire surface of the casserole.
  8. Bake, uncovered, for 25-30 minutes, or until the topping is deeply golden brown and the filling is bubbling around the edges.
  9. Let the casserole rest for 10 minutes before serving. This allows the sauce to thicken to the perfect consistency.

Notes

For the best texture, do not skip the 10-minute rest after baking. Use thick-cut ham for better texture that doesn't disappear into the sauce. Leftovers can be stored in an airtight container in the refrigerator for up to 3 days; reheat in the oven to help maintain the topping's crunch. For a lighter version, you can use reduced-fat milk and cheese, though the sauce may be slightly less rich.