Preheat your oven to 350°F (175°C).

Carefully slice your 18-inch loaf of French bread horizontally.

In a small bowl, combine 3 tablespoons of softened butter, 2 tablespoons of grated Parmesan, ½ teaspoon of garlic powder, and ¼ teaspoon of salt.

Generously spread the garlic butter mixture over the cut side of the top half of the bread.

On the bottom half of the bread, layer 8 ounces of ham, 2 ounces of pepperoni, 2 ounces of salami, and 4 ounces of provolone cheese.

Place the assembled sandwich in the preheated oven and bake for 8-10 minutes.

Optionally, switch to broil for an additional 1-2 minutes for extra crispiness.

Whisk together ¼ cup of mayonnaise, 1 tablespoon of red wine vinegar, 1 teaspoon of Italian seasoning, ½ teaspoon of salt, ½ teaspoon of black pepper, and another ½ teaspoon of garlic powder in a bowl.

Gently fold in 8 ounces of shredded lettuce, ½ cup of diced tomatoes, and ½ cup of sliced pepperoncini to the dressing.

Assemble the sandwich by piling the salad mixture on the bottom half and placing the top half over it.