Slice the Italian roll lengthwise, but not completely through; leave a hinge.
Spread 1-2 tablespoons of herbed mayo on the roll.
Layer the cheese, ham, salami, tomato, onion, shredded lettuce, and pepperoncini. Close the sandwich tightly.
Wrap securely in saran wrap. Chill until serving.
Notes
Make Ahead: Prepare the sandwiches, minus the mayo, wrap well in plastic or a beeswax wrapper and store in the fridge or in a cooler until serving. Serve the herbed mayonnaise on the side.If you prefer, you can add Italian salad dressing instead of the mayo or in addition to it.Promptly store leftovers in an airtight container in the refrigerator, for up to 3 days.Nutritional values are approximate and based on 1 sandwich.Variations: You can change the combinations of the meat to suit your preferences or to copycat your favorite Subway or Jersey Mike's sandwich.
For an Italian BMT: add sliced pepperoni.
For a Cold Cut Combo: add bologna.
For a Jersey Shore's Favorite: sub capicola for the salami.
For a Super Sub: sub capicola for the salami and add prosciutto.