Preheat the oven to 350°F.

In a large bowl, combine the ground chicken, breadcrumbs, egg, garlic powder, onion powder, thyme, salt, and black pepper. Mix until well combined.

In a separate bowl, mix the diced ham, shredded Swiss cheese, and chopped parsley.

On a large sheet of parchment paper or wax paper, shape half of the chicken mixture into a rectangle about 1 inch thick. Spread the ham and cheese mixture evenly over the chicken layer, leaving a small border around the edges.

Carefully roll the meatloaf from one long side to the other, using the parchment paper to help. Pinch the ends to seal. Place the rolled meatloaf seam-side down in a greased baking dish.

In a small bowl, whisk together the milk and Dijon mustard. Pour this mixture over the top of the meatloaf.

Bake in the preheated oven for 1 hour, or until the internal temperature reaches 165°F. Let it rest for 10 minutes before slicing.