Preheat the oven to 375°F (190°C).
Prepare the garlic butter mixture.
Slice the French bread in half lengthwise.
Spread the garlic butter evenly over the cut sides of the bread.
Bake the bread for 10-12 minutes until slightly golden.
In a skillet, heat olive oil over medium heat.
Add the steak, onions, and bell peppers to the skillet.
Season with salt and pepper, then cook until steak is browned.
Remove the skillet from the heat and stir in the provolone cheese.
Spoon the cheesesteak mixture onto the baked bread.
Return the bread to the oven and bake for another 5-10 minutes.
Remove from the oven and let cool slightly before slicing.