01 -
Brown the chopped bacon in a skillet over medium heat until crisp. Transfer to a paper towel-lined plate and reserve 1 tablespoon for topping. Pour off all but 1 tablespoon of bacon fat.
02 -
Cook the onion and mushrooms in the reserved bacon fat until soft and the mushrooms have released their moisture, about 5 minutes. Let cool for 5 minutes.
03 -
In a large bowl, combine the ground beef, cooled vegetables, most of the bacon, about two-thirds of the Swiss cheese, the egg, milk, breadcrumbs, Worcestershire sauce, salt, and pepper. Mix gently with your hands just until blended.
04 -
Form the mixture into a compact loaf on a foil-lined rimmed baking sheet or in a loaf pan.
05 -
Bake at 350°F (175°C) for 55 to 60 minutes until the internal temperature reaches 160°F (71°C).
06 -
Drain excess fat. Sprinkle the remaining Swiss cheese and reserved bacon over the top. Bake for 5 minutes more until the cheese is melted and bubbling.
07 -
Let the meatloaf rest for 10 minutes before slicing. This keeps the juices inside and helps the slices hold their shape.