In a large mixing bowl, whisk together mayonnaise, red wine vinegar, garlic powder, and oregano until smooth. Season with salt and pepper to taste, then fold in shredded lettuce, sliced red onion, and banana peppers.

Take four sub rolls and slice them open. Layer each roll with salami, pepperoni, and turkey, distributing the meat evenly. Top with provolone cheese.

Preheat your broiler to high. Place the assembled sandwiches on a baking sheet lined with parchment paper and broil for 2-3 minutes until the cheese melts and edges crisp.

Remove hot sandwiches from the oven. Layer slices of tomatoes on top of the melted cheese, seasoning lightly with salt and pepper. Spoon grinder salad mixture on each sandwich.

Sprinkle each sandwich with grated parmesan cheese. Press down gently, then slice in half if desired. Serve immediately.