Meatloaf:

1. Preheat Oven: Preheat your oven to 375°F (190°C). Line a loaf pan with parchment paper or lightly grease it.
2. Prepare Meatloaf Mixture: In a large bowl, combine the ground chicken, breadcrumbs, Parmesan cheese, Swiss cheese, beaten egg, Dijon mustard, garlic powder, onion powder, salt, and black pepper. Mix gently until just combined.
3. Form Meatloaf: Press the mixture into the prepared loaf pan, shaping it into a loaf.
4. Bake: Place the meatloaf in the oven and bake for 35-40 minutes, or until the internal temperature reaches 165°F (74°C).

Creamy Mushroom Sauce:

1. Sauté Mushrooms: While the meatloaf is baking, heat the butter and olive oil in a skillet over medium heat. Add the sliced mushrooms and cook until browned and tender, about 5-6 minutes.
2. Add Garlic: Add the minced garlic and sauté for another minute until fragrant.
3. Add Broth and Cream: Pour in the chicken broth, bring to a simmer, then add the heavy cream. Stir well and let it cook for about 5 minutes until the sauce thickens slightly. Season with salt and pepper to taste.
4. Optional Cheese Addition: For a richer sauce, stir in 1/4 cup of shredded Swiss cheese until melted and creamy.

Serve:

1. Serve with Sauce: Once the meatloaf is done, let it rest for 5 minutes before slicing. Spoon the creamy mushroom sauce over each slice before serving.