In a large bowl, combine chopped lettuce, red onion, pepperoncini, tomatoes, cucumbers, salami, turkey, ham, and provolone cheese.
In a separate bowl or jar, whisk together mayonnaise, Greek yogurt, red wine vinegar, pepperoncini juice, parmesan cheese, garlic powder, oregano, salt, and pepper until smooth.
Pour the dressing over the salad ingredients.
Toss everything together until evenly coated.
Serve immediately and enjoy!