Divide onions between the patties and, using the spatula, chop the meat and the onions into smaller pieces.
Place 2 slices of cheese on each portion of chopped-up patty and continue to cook until the cheese has melted, about 1 minute. (You can speed up this process by mixing the cheese in with the chopped beef and onion).
Spread the toasted hoagie rolls with mayonnaise and fill (or stuff) with the chopped burger, tomato slices, and shredded lettuce. Wrap the chopped cheese in deli paper and cut in half or serve whole.

Nutrition

Calories per Serving 296
Total Fat 24.5 g
Saturated Fat 9.6 g
Trans Fat 0.8 g
Cholesterol 58.6 mg
Total Carbohydrates 7.3 g
Dietary Fiber 0.8 g
Total Sugars 1.2 g
Sodium 282.5 mg
Protein 11.7 g