Preheat the oven to 350 degrees F. In a small bowl soak the bread in milk for a few minutes. While the bread is soaking, cut 1 bacon slice in small pieces. Sauté with the olive oil in a medium saucepan over medium-high heat until the fat has rendered. Add the onion, carrot, and celery and sauté for five minutes, or until the vegetables are soft. Add the garlic and sauté for 2 minutes or more, then remove from the heat. Transfer the vegetables to a bowl to cool.

In a large mixing bowl, use your hands to combine the beef, pork, and veal with the salt and pepper. Add the eggs, ketchup, mustard, and cheese. Pick the bread out of the milk and squeeze out the excess milk into a small bowl. Squish the bread mixture into the meat mixture. Add the cooled vegetables and combine. The meat mixture should be pretty gooey. Add some of the squeezed bread-milk if you need more moisture.

Form the mixture into a loaf on a sided baking sheet lined with aluminum foil. Drape the remaining bacon slices over the top of the loaf. Bake for an hour, or until thermometer registers 165 degrees F. Let loaf stand for 10 minutes before slicing. Serve with ketchup or chili sauce