Preheat oven to 180°C.
Mix the beef mince, grated onion, egg and the contents of the sachet of Knorr Saucy Meatballs Dry Cook-in-Sauce (no need to add water) together and shape into patties.
Refrigerate for 10 minutes.
Heat a tablespoon of oil in a heavy-based frying pan and sauté the sliced onions until soft and sticky, adding a pinch of sugar and salt (to taste).
Heat the rest of the oil in the same pan and fry the burger patties for about 4 minutes then transfer to an oven tray and cook in a preheated oven for about 12 minutes or until cooked through.
Butter the hamburger buns and layer with lettuce leaves, sliced tomato, beef patties, cheese, bacon and cooked onions.
Serve with various condiments such as barbeque sauce and tomato sauce.