In a medium bowl, whisk together all of the dressing ingredients. Cover and chill for up to 2 days.
ASSEMBLE THE SALAD:
In a large bowl, combine the lettuce, olives, onion and cheese. Add enough dressing to coat the lettuce, tossing gently. Sprinkle with croutons, and serve with remaining dressing on the side.
Notes
Nutritional information does not include the (optional) croutons.
If serving this recipe as GLUTEN-FREE, leave off the croutons and make sure you're using a brand of mayonnaise that is known to be GF.