Preparing: Heat oven to 350ºF [175 ºC]. Spread the bacon covering the bottom and sides of a medium bread mold. Set aside two strips of bacon for later use.
Seasoning the meat: Mince the remaining bacon. In a large bowl, combine the bacon, onion mixture and tomato sauce with the minced beef. Knead with your hands to mix thoroughly (remember to wash your hands carefully before and after to prevent cross-contamination).Mix in the egg with a spatula, followed by parsley, bell pepper, and tomato, and mix until combined.
Making the albondigón: Place the meat mixture beef in the bread mold, and form an elongated meatball on top of the bacon. Wrap the meatball with the bacon, making sure the slices of bacon overlap.
Cooking: Cover the mold tightly with aluminium foil and cook in the oven for 25 mins.Remove from the oven and discard the aluminum foil. Return to the oven and increase heat to 450 ºF [230 ºC]. Cook for another ten minutes, or until the bacon turns golden brown and has crispy edges.
Serving: Let it rest for five minutes before slicing, garnish with parley, then serve.