Everyone in our family loves this

1. Prepare Ingredients: Slice onions, bell pepper, garlic, and steak.
2. Sauté Vegetables: Heat olive oil in a skillet. Add onions and bell pepper. Cook until softened. Add garlic and mushrooms. Cook until tender.
3. Add Steak: Add sliced steak to skillet. Cook until heated through.
4. Prepare Bread: Butter one side of each bread slice. Spread mayo on the other side.
5. Assemble Sandwich: Place provolone cheese on mayo side of one bread slice. Add steak and vegetable mixture. Top with remaining provolone cheese and the other bread slice (mayo side down).
6. Cook Sandwich: Heat a skillet over medium heat. Cook sandwich until golden brown and cheese is melted.
7. Serve: Enjoy immediately!

Optional: Add mushrooms for extra flavor.