In a bowl, combine large pimento-stuffed olives, pitted black olives, giardiniera, marinated roasted red peppers, garlic, extra-virgin olive oil, red wine vinegar, capers, black pepper, and celery salt. Mix well until everything is evenly coated.

Take your Italian bread loaf and slice it in half horizontally, ensuring both halves are ready to be filled with deliciousness.

Start with the bottom half of the bread. Lay down slices of mozzarella cheese, Genoa salami, provolone cheese, mortadella or deli ham, and capicola, creating a beautiful and hearty base.

Spoon the prepared olive salad mixture generously over the layered cheeses and meats, spreading it evenly so every bite is packed with flavor.

Place the other half of the bread on top and press down gently. This will help meld the flavors together beautifully.

Cut the sandwich into wedges, serving each piece with optional pickled pepperoncini and crispy potato chips for a delightful crunch if desired.