To make the dressing combine all ingredients in a blender. Blend until smooth. Pour into a container and refrigerate until ready to serve the salad.
To make the salad wash and pat dry the lettuce. Place in a large bowl.
Scatter the tomatoes, onions, and black olives over top of the lettuce.
Place the croutons around the outer edge of the lettuce.
Put the pepperoncini peppers on top of the lettuce in the middle of the bowl.
Sprinkle the top with Parmesan cheese.
Either serve with the dressing on the side or pour the dressing over the top of the lettuce and toss to combine.
Serve immediately.