Preheat your oven to 400°F (200°C). Slice the Italian bread in half lengthwise and place both halves cut side up on a baking sheet.

Heat 1 tablespoon of olive oil in a skillet over medium-high heat. Add the ribeye steak and season with salt and pepper. Cook for 3-4 minutes, stirring occasionally, until browned and cooked through. Transfer to a plate and set aside.

In the same skillet, add the remaining 1 tablespoon of olive oil. Add the sliced onions and cook over medium heat for 10-15 minutes, stirring occasionally, until golden brown and caramelized. Add the minced garlic in the last minute and cook until fragrant.

Spread the cooked steak evenly over both bread halves. Top with the caramelized onions and garlic, then sprinkle the shredded cheese over everything. Add optional toppings like bell peppers, mushrooms, or jalapeños if desired.

Bake in the preheated oven for 10-12 minutes until the cheese is melted, bubbly, and golden, and the edges of the bread are crispy. Watch closely in the last few minutes to prevent burning.

Remove from the oven and let cool for 2-3 minutes. Slice into portions and serve hot.