Preheat your oven to 350°F (175°C).

Pound the chicken breasts between two sheets of plastic wrap to an even thickness of about 1/4 inch. Season with salt and pepper.

Layer slices of Swiss cheese and cooked ham on each chicken breast.

Roll the chicken breasts tightly, securing with toothpicks.

Set up a dredging station with flour, beaten eggs, and panko breadcrumbs in shallow bowls.

Coat each chicken roll in flour, then dip in eggs, and finally roll in panko breadcrumbs.

In a skillet, heat butter and olive oil over medium heat. Brown the chicken rolls for about 5 minutes per side until crispy.

Transfer the chicken rolls to a baking dish and bake for 20-25 minutes until cooked through.

In the same skillet, prepare the creamy sauce by melting butter and whisking in flour, then gradually adding milk and stirring in Parmesan cheese and Dijon mustard.

Serve the chicken warm, drizzled with creamy sauce.