Preheat the Oven:

Preheat your oven to 375°F (190°C).

Line a baking sheet with parchment paper or lightly grease it.

Prepare the Garlic Butter:

In a small bowl, combine the softened butter and minced garlic. Mix well.

Cut the loaf of bread in half lengthwise and spread the garlic butter evenly over both halves. Place the bread halves on the prepared baking sheet, cut side up.

Cook the Vegetables and Steak:

In a large skillet over medium-high heat, add a drizzle of oil (if needed) and sauté the sliced bell pepper and onion until tender and slightly caramelized, about 5-7 minutes. Remove from the skillet and set aside.

In the same skillet, add the thinly sliced steak and cook until browned and cooked through, about 3-5 minutes. Season with salt, pepper, and Worcestershire sauce. Remove from heat.

Assemble the Cheesy Bread:

Evenly distribute the cooked bell pepper, onion, and steak over the garlic buttered bread halves.

Sprinkle the shredded provolone cheese, mozzarella cheese, and grated Parmesan cheese evenly over the top of the steak and vegetables.

Bake:

Bake in the preheated oven for 15-20 minutes, or until the cheese is melted and bubbly and the bread is crispy.

Serve:

Remove from the oven and let cool slightly.

Garnish with chopped fresh parsley if desired.

Slice the cheesy bread into pieces and serve warm.