How to Make It
Preheat oven to 350°F.
Place bread on one half of a rimmed baking sheet. Toss with 1 tablespoon oil and 1/8 teaspoon salt, and spread in a single layer. Place chickpeas on opposite half of baking sheet; toss with paprika, 1/8 teaspoon salt, and remaining 1 teaspoon oil, and spread in a single layer. Bake at 350°F for 20 minutes, tossing once halfway through.
Transfer bread to a food processor. Pulse until ground. Set aside.
Whisk together yogurt, lemon juice, mustard, Worcestershire sauce, garlic, anchovy paste, pepper, and remaining 1/4 teaspoon salt in a bowl. Whisk in water, 1 teaspoon at a time, until dressing reaches desired consistency. Set aside.
Preheat a grill to medium-high (about 450°F), or heat a grill pan over medium-high. Coat cut sides of romaine hearts with cooking spray. Place 3 or 4 romaine quarters, cut sides down, on grill grate or in grill pan. Grill until charred, about 2 minutes, turning after 1 minute and watching closely to prevent burning. Repeat with remaining romaine quarters.
Place 2 romaine quarters on each of 4 plates. Top with 2 tablespoons Caesar dressing, 1/4 cup sourdough breadcrumbs, 1/4 cup chickpeas, and 1 tablespoon cheese.