Muffuletta Sandwich

INGREDIENTS

• 2 teaspoons dried oregano
• 2 tablespoons extra-virgin olive oil
• 1/2 cup sliced pickled cocktail onions
• 16-ounce container giardiniera (assorted pickled vegetables), drained and chopped
• 2 ounces deli ham, sliced
• 3 anchovy fillets, chopped
• 1/4 cup drained tiny capers in brine
• 2 ounces mortadella, sliced
• 1 cup sliced marinated artichoke hearts
• 2 ounces capicola, sliced
• 2 ounces Genoa salami, sliced
• 1/2 cup pitted chopped kalamata olives
• 1/2 cup shredded inner stalks celery
• 2 tablespoons red-wine vinegar
• 8- inch round muffuletta bread, split open
• 1/2 cup finely chopped pitted green olives
• 2 ounces provolone, sliced
• 1/4 teaspoon peperoncino flakes
• 1/2 cup seeded, finely chopped pickled Tuscan peperoncini
• 1/2 cup finely chopped roasted red peppers
• 1/2 cup shredded carrot
• 2 ounces low-moisture mozzarella, sliced