Preheat oven to 350�F.
In a rimmed baking sheet, cover fully with tin foil, place parchment paper over top.
In a small skillet, Heat oil over medium heat. Cook the onion until it becomes translucent - about 2 minutes. Add garlic, stirring occasionally, until very soft, about 2 additional minutes. Take skillet off heat and transfer contents into a large bowl.
Wipe down the skillet then add the ketchup, mustard, vinegar, brown sugar, and cayenne to a boil. Reduce heat, and simmer, stirring occasionally, until slightly reduced and thickened, about 5 minutes. Transfer 2 tablespoons skillet contents to the food processor. Add broth and parsley and blend until smooth.
Add broth mixture, eggs, breadcrumbs, Parmesan, salt, and pepper to onion and garlic in the large bowl; mix thoroughly to combine. Add beef and mix well using your hands to fully coat.
Transfer meatloaf to prepared pan and form into a long log, smoothing it out as you form it.
Spread remaining skillet contents over top of the beef, and drape bacon in a crisscross pattern over top, making sure to tuck the ends under the meat.
Bake for roughly an hour and 20 minutes, or until internal beef temperature reaches 165�F and bacon becomes crisp.
Let rest 10 minutes before slicing.