Preheat your oven to 350°F (175°C).
Separate the tops and bottoms of the slider rolls and place the bottoms in an 11" x 7" baking dish or on a baking sheet. Spread a thin layer of mayonnaise on the tops and bottoms of the rolls.
In a skillet, cook the thinly sliced steak with salt, pepper, garlic powder, and onion powder. Once cooked, drain off any excess liquid and set aside.
Sauté the diced green pepper and onion until tender. Drain off any excess liquid and set aside.
Evenly spread the cooked steak, sautéed peppers, and onions over the bottom pieces of bread in the baking dish.
Layer the provolone cheese slices over the peppers and onions.
Place the top pieces of bread over the cheese.
In a small bowl, combine the melted butter and finely diced raw onion. Brush the tops of the bread with this butter mixture.
Cover the baking dish with foil and bake for 10 minutes. Then, remove the foil and continue baking for another 10 minutes or until the cheese is melted and bubbly.
Once baked, cut into sliders and serve hot. Enjoy!