Sprinkle the chicken breasts with salt, pepper, garlic powder, and onion powder, tossing to coat evenly.
On a cutting board, place a chicken breast between two sheets of plastic wrap and pound until about ½ inch thick with a meat mallet, rolling pin, or heavy pan.
Remove the plastic wrap and place a layer of Swiss cheese, then ham, then one more layer of Swiss cheese.
Evenly roll the chicken, and place onto a new sheet of plastic wrap.
Wrap the chicken in the plastic wrap, twist the excess plastic, and roll the chicken while twisting the sides in to tighten and firm up the roll of chicken cordon bleu. Tie the excess and chill in the fridge to set for 30 minutes.
After the rolls are set, prepare large, wide dishes with flour, beaten egg, and bread crumbs, and dredge the chicken in the flour, egg, and bread crumbs.
Place the breaded chicken cordon bleu in a 325°F (170°C) pot of oil, and cook about 5 minutes per side or until the outside is an even golden brown. If a good color is achieved and the chicken’s center is still not 165°F (74°C), you can finish the chicken in an oven at 325°F (170°C) until that temperature is reached.
In a small pot on medium heat, melt the butter and cook the garlic until soft.
Add in flour, and whisk for 1 minute.
Add in the milk, and whisk until fully combined with the roux. 6. Continue whisking until the mixture comes to a simmer and has thickened.
Add in the Dijon mustard, salt, pepper, and Parmesan cheese. 8.Whisk to combine. Set aside.
Slice chicken and drizzle with Dijon sauce. Enjoy!