Chicken Caprese Sandwich

extra virgin olive oil, divided, plus more for drizzling

fresh parsley, minced

lemon, juiced

kosher salt and freshly ground black pepper

skinless, boneless chicken breasts

loaf of sourdough bread (I used rosemary flavored), cut in half lengthwise

log fresh mozzarella cheese, sliced into ¼ inch rounds

medium size or campari tomatoes, about 11 ounces

fresh basil leaves

balsamic vinegar or balsamic glaze