In a skillet, cook the bacon until crispy, then crumble it.
In the same skillet, sauté the chopped onions and mushrooms until softened. Set aside to cool.
In a large bowl, combine the ground beef, ground pork, breadcrumbs, milk, Parmesan cheese, cooked bacon, shredded Swiss cheese, sautéed onions, and mushrooms.
Add the eggs, Worcestershire sauce, 1 tablespoon of ketchup, garlic powder, thyme, salt, and pepper. Mix gently until just combined.
Shape the mixture into a loaf and place it in a greased baking dish.
Spread the remaining 1/2 cup of ketchup evenly over the top.
Bake for 60-70 minutes or until the internal temperature reaches 160°F (71°C).
Let the meatloaf rest for 10 minutes before slicing. Serve warm.
Notes
Servings assumed at 4 (not specified in original source). Prep time estimated at 20 minutes (not specified in original source); cook time reflects the midpoint of the source's 60-70 minute range. Leftovers keep refrigerated up to 4 days or frozen up to 3 months. Reheat gently with a splash of broth or extra ketchup to keep slices moist.