Grilled Ham, Cheese, and Salami with Caper Relish

INGREDIENTS

• 1 cup thinly sliced iceberg lettuce
• 1 rectangular 10x7x1 1/2-inch bread loaf (such as ciabatta)
• 4 teaspoons minced fresh oregano
• 1/2 cup olive oil
• 3 tablespoons capers, chopped
• 3 tablespoons finely chopped pitted brine-cured green olives
• 4 ounces sliced Italian Genoa salami
• 3 tablespoons white wine vinegar
• 1 large shallot, minced
• 3 ounces sliced provolone cheese
• 3 tablespoons minced peperoncini
• 3 tablespoons butter, room temperature
• 4 ounces sliced Black Forest ham
• 3 ounces Teleme or Fontina cheese, grated (about 1 cup)