Prepare a grill for indirect heat. If using a charcoal grill, build the hot coals on one side only. If using a gas grill, heat one side only to medium-high heat.
Using a fork or paring knife, prick the onion all over to allow the smoke to penetrate. Place the onion directly onto the coals and cook until charred and softened, about 5 minutes. Remove from the coals and when it is cool enough to handle, peel and finely chop.
Add the onions, garlic, oregano, olive oil and red wine vinegar to a glass jar with a lid. Season with salt and pepper, then shake vigorously and set aside.
Add the lettuce, chickpeas, salami, provolone, tomatoes and pepperoncinis to a large bowl. Dress with some of the smoky red wine-oregano vinaigrette and toss to coat. Add the Parmesan all over the top and serve with freshly cracked black pepper.