Make-Ahead Chicken Cordon Bleu Casserole

Chicken cordon bleu is one of those dishes I've always wished I could make, but have never really felt up to the challenge.  It just felt like too much work to bread giant rolls of meat and cheese.  But when I spied this recipe for a make-ahead, one-dish version that included potatoes, it intrigued me.  While it, too, represents a good amount of work, it's not difficult -- it just takes a little time.  The fact that it can be made ahead is a big bonus in my book.  I  made it the night before and let it sit in my refrigerator the next day, baking it just before serving.

MAKE-AHEAD CHICKEN CORDON BLEU CASSEROLE
Printable version of this recipe

Bread Crumb Topping
4 slices white sandwich bread
2 T butter, melted

Casserole
2 lbs chicken breast tenderloins or tenders (Note:  you can also use regular boneless, skinless chicken breasts.  I find that the tenderloins are the perfect size for this.)
8 ounces of smoked deli ham
4-5 Yukon Gold or russet potatoes, peeled and sliced 1/8" thick
1 t salt
4 T butter
1 medium onion, chopped
1 t dried thyme
3 medium garlic cloves, finely minced
6 T all-purpose flour
2 c low-sodium chicken broth
3/4 c heavy cream or milk
6 ounces Swiss cheese, shredded, about 2 cups
2 T Dijon mustard
1/4 teaspoon cayenne pepper


DIRECTIONS:

For the topping, process the bread and butter in a food processor until coarsely ground. Set aside.

For the filling, preheat the oven to 400 degrees, making sure the oven rack is in the middle. Place the potatoes, 6 cups water and 1 teaspoon salt in a large pot. Bring to a boil over high heat, then reduce the heat to a simmer and cook, uncovered, until the potatoes are partially cooked, about 2 minutes (don’t overcook because they will continue to cook in the oven!). Carefully drain potatoes, or remove them with a slotted spoon, and transfer them to a bowl. Set aside.

Meanwhile, melt the 4 T of  butter in a medium saucepan over medium heat. Add the onion, thyme, and 1/2 teaspoon salt. Cook until the onions are softened, about 6 minutes. Add the garlic and cook until fragrant, stirring constantly, about 1 minute. Add the flour and cook, stirring constantly, until golden, about 1 minute (this helps cook out the flour taste in the roux). Slowly whisk in the chicken broth and the cream or milk. Bring the mixture to a simmer, whisking often, until slightly thickened (if using milk instead of cream, you may have to cook longer for it to thicken up a bit). Off the heat, whisk in the Swiss cheese, Dijon, and cayenne pepper until smooth. Season with salt and pepper to taste. Cover and set aside until ready to use.  (Note:  you may be tempted to skip the cayenne because of the spiciness attached to it.  Don't worry.  There is little heat with it in this recipe and it brings a certain something to the flavor that can't be duplicated any other way.)

Toss the potatoes with half of the sauce and spread into the bottom of a lightly greased 9X13-inch baking pan. I like to line the pan with foil for easy cleanup.  Use a meat mallet to pound the chicken into thin pieces.  Lay chicken on top of the potatoes in a single layer so it will cook evenly.  Top with a layer of ham.  I like to have the deli slice the ham very thinly, and then I cut it into smaller pieces and layer it on top of the chicken.  This is so it will scoop out easily when serving.  Pour the remaining sauce evenly over the chicken and sprinkle with the bread crumb topping.

At this point, I cover the casserole and place it in my refrigerator overnight.  I do not have any problems with the cheese sauce clumping up during the baking process; it reheats smoothly.  However, others have recommended that if you want to store the casserole, you should not add the cheese sauce or bread crumbs to the top.  Instead, prepare the casserole through the step of layering the ham and stop.  Store the remaining cheese sauce and bread crumbs in separate containers, and add just prior to baking.

When ready to bake, remove from the refrigerator and heat in a 400-degree oven for 45 minutes.  Bake until the chicken is cooked through and the casserole is bubbling.  Cool for 10 minutes before serving.

If you wish to bake it immediately after preparing, decrease the baking time by about 10 minutes.  Bon appetit!

Original recipe from Cook's Illustrated by way of Mel's Kitchen Cafe