By adding roast beef, grilled onions and peppers to your grilled cheese, you achieve the taste of a Philly cheese steak. The meat and cheese is piled high on this grilled cheese and makes for a filling sandwich.
Heat olive oil in a pan.
Add onion, pepper, mushrooms and salt & pepper; and sauté' for 4-5 minutes on medium-high heat.
Transfer mixture to a paper towel to absorb moisture.
In another pan, add unsalted butter. Let it melt on low heat. Place two slices of toast (medium-low heat)
Mix together: mayonnaise and hot sauce. Spread evenly on both slices.
Place 2 slices of cheese on each slice. Roast beef (any type/kind), 2-3 slices on each slice of the toast. Spoon in sautéed onion, pepper and mushroom.
Flip the other side on top, and allow to toast for 1-2 minutes on each side.
Turn the heat on low, and cover with the lid. Every few minutes, uncover and turn the sandwich over. Until the cheese is completely melted.