1. Preheat your oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish.
2. Cook the pasta in a large pot of salted boiling water according to package directions until al dente. Drain and set aside.
3. While the pasta cooks, heat a large skillet over medium heat and add the chicken pieces. Season with salt, pepper, and garlic powder. Cook, stirring occasionally, until the chicken is golden and cooked through, about 6-8 minutes. Remove from heat.
4. In the same skillet, melt the butter over medium heat. Whisk in the flour and cook for about 1-2 minutes until it forms a smooth roux and begins to bubble but doesn’t brown.
5. Gradually whisk in the milk, stirring constantly to avoid lumps. Add Dijon mustard, nutmeg, and a pinch of salt and pepper. Cook for 5-7 minutes, stirring frequently, until the sauce thickens and coats the back of a spoon.
6. Remove the sauce from heat and stir in the Swiss, mozzarella, and Parmesan cheeses until melted and smooth.
7. In a large mixing bowl, combine the cooked pasta, chicken, chopped ham, and cheese sauce. Mix gently to combine all the ingredients evenly.
8. Transfer the mixture into the prepared baking dish and sprinkle additional shredded Swiss or mozzarella cheese on top.
9. Bake uncovered for 20-25 minutes, or until the top is bubbly and golden brown.
10. Remove from oven and let it rest for 5 minutes before serving. Garnish with freshly chopped parsley if desired.

One of my favorite things about this recipe is how forgiving it is. I’ve made it with leftover chicken, swapped the ham for turkey, and even doubled the cheese for extra indulgence. It always turns out fantastic, which means less stress and more time sitting around the table with my family.