Optional: small (½-inch) diced stale bread, buns or pita (about 3 to 4 ounces) • olive oil, plus more for drizzling • Kosher salt and black pepper • romaine hearts • can chickpeas, rinsed • dry chickpeas, cooked • large English cucumber, halved lengthwise, seeded and diced • pitted olives, roughly chopped (about 3 ounces) • scallions, thinly sliced • red wine vinegar • drained capers, roughly chopped • shallot, minced •