Classic Muffaletta Sandwich Recipe

Name: Classic Muffaletta Sandwich Recipe
Ingredients: For the Olive Salad; 1 cup pitted olives, preferably a mix, roughly chopped; 1 tablespoon minced shallots; 1 tablespoon minced celery; 1/2 cup roasted red pepper strips; 2 tablespoons capers, rinsed, dried, and roughly chopped; 2 to 3 Italian hot pickled peppers (such as pepperoncini), chopped (optional); 3 tablespoons olive oil; 1 tablespoon red wine vinegar; Kosher salt and freshly ground black pepper; For the Sandwich; 1 loaf focaccia, halved lengthwiseok; 4 ounces salami, thinly sliced; 4 ounces capicola, thinly sliced; 4 ounces mortadella, thinly sliced; 4 ounces provolone cheese, thinly sliced