In a small bowl, stir together the oats and milk. Thinly slice 1/4 of the onion and set aside. Finely chop the remaining onion. In a large bowl combine the turkey, oat mixture, chopped onion, bell pepper, eggs, Worcestershire sauce, ketchup, salt and a few grinds of pepper.
Mix just until well combined.
Transfer the mixture to a 9 by 13-inch baking dish and shape into a loaf about 5 inches wide and 2 1/2 inches high. Pour the tomato sauce over the meatloaf and sprinkle with the sliced onions. Bake for about 1 hour or until an instant-read thermometer registers 160 degrees.F.
Remove from the oven and let rest for 10 to15 minutes before slicing.
For the meatloaf: Preheat the oven to 350 degrees F.
Pour the milk over the bread and allow it to soak in for several minutes. Place the ground beef, milk-soaked bread, Parmesan, salt, some pepper, seasoned salt and parsley in a large mixing bowl. Pour in the eggs. With clean hands, mix the ingredients until well combined.
Form the mixture into a loaf shape on a foil-lined broiler pan, which will allow the fat from the meat to drain.
Lay the bacon slices over the top, tucking them underneath the meatloaf to give the meatloaf some support.
Next, make the tomato sauce: Pour the ketchup into a bowl. Add the brown sugar and dry mustard, and splash in the hot sauce and Worcestershire sauce. Stir the mixture until well combined. Pour one-third of the sauce over the top of the meatloaf.
Bake for 45 minutes, and then pour over another one-third of the remaining tomato sauce over the meatloaf. Bake for an additional 20 to 25 minutes; the meatloaf should be no longer pink in the middle. Allow to sit 10 minutes before serving.
Serve with the remaining tomato sauce on the side as a dipping sauce.