In a bowl, combine mayo, red wine vinegar, kosher salt, black pepper, oregano, red pepper flakes, and minced garlic until smooth and well-mixed.

Fold in sliced pepperoncini, freshly grated Parmesan, red onion, and lettuce into the mayo mixture, tossing gently with tongs until everything is evenly coated. Set this delightful mix aside.

Set your oven to 425°F. While it warms, slice the loaf of crusty Italian bread in half. Layer muenster and provolone cheese on both sides, toasting until bubbly and golden—this should take about 3-4 minutes.

Layer the meats on top of the melted cheese, arranging them fluffy and ruffled, not flat. Toast again for an additional 3-4 minutes until the meat is warm and the bread is beautifully crisp. Sprinkle some fresh Parmesan on top before removing from the oven.

Top the meats with slices of juicy beefsteak tomato, drizzling olive oil and seasoning with salt and pepper to taste, creating a flavorful base.

Finally, pile that vibrant lettuce mixture atop the tomatoes, add more grated Parmesan for a touch of decadence, and place the top piece of bread on. Slice and serve! Enjoy each bite of your scrumptious Italian Grinder Sandwich.