Ingredients:

• 6 pepper bell peppers, assorted colors
• 3 tablespoons olive oil, divided
• 1 large white onion, thinly sliced
• 8 ounces cremini mushrooms, stems trimmed and thinly sliced
• 1 teaspoon salt, divided
• 3/4 teaspoon freshly ground black pepper, divided
• 2 pounds sirloin steak, thinly sliced
• 9 slices provolone cheese
• 1 tablespoon fresh thyme leaves, for garnish