1-Getting this chicken cordon bleu casserole just right involves a few simple steps that anyone can follow. Start by preheating your oven to 350°F to make sure everything bakes evenly from the start. Spread the 5 1/2 cups of shredded rotisserie chicken in a 9×13 inch casserole dish as your base layer, then add the 2 cups of cubed ham on top.

2-Next, make the creamy cheese sauce by melting 4 tablespoons of butter in a pan over medium heat. Whisk in 1/4 cup of all-purpose flour and cook for a minute, then slowly pour in 2 cups of milk while stirring to avoid lumps. Add 1 tablespoon of Dijon mustard, 1 tablespoon of lemon juice, 1/2 teaspoon of garlic powder, and 1/4 teaspoon of salt, letting it simmer until it thickens.

3-Stir in 1 1/4 cups of shredded Swiss cheese and 1/4 cup of grated Parmesan cheese until smooth, then pour this sauce evenly over the chicken and ham layers. For the topping, mix 1 cup of Panko breadcrumbs with 2 tablespoons of melted butter and sprinkle it over the casserole. Bake for 30 to 35 minutes until it’s golden and bubbly, then let it cool for 5 to 10 minutes before serving to eight people.