For the dressing: In a blender, add the olive oil, mayonnaise, Parmesan, parsley, sugar, vinegar, black pepper, salt, red pepper flakes, garlic and lemon juice and blend until pureed.
For the salad: Put the romaine and iceberg greens in a large bowl and toss with the dressing. Top the salad with the pepperoncini, olives, tomatoes and onions. Sprinkle with Parmesan at the end.
Recipe courtesy of Ree Drummond