Place the oven grill in the center. Preheat the BBQ to maximum heat, or the oven at 230 °C (450 °F).
Cut the bread lengthwise. Grill the bread on the BBQ or place on a baking tray in the oven and cook for 5 minutes. Set aside.
In the meantime, heat the oil over medium heat in a pan. Cook the onion for one minute.
Add the beef and cook for 4 to 5 minutes while breaking it up into pieces with a wooden spoon until all the meat is browned.
Add the ketchup, the chili sauce, the mustard, the Worcestershire sauce, and the tomato paste. Salt and pepper to taste. Mix well and cook for 10 minutes over medium-low heat.
Place the meat preparation on one half of the bread. Garnish with Armstrong shredded cheese and put back in the oven for another 5 minutes.
Remove from the oven and separate the Sloppy Joes into portions.
