Ranch Dressing

This may sound stupid but I visit a Greek owned restaurant that serves some of the best Ranch dressing and I can't get their recipe. I feel sure it's homemade and not bottled because most of what I've found bottled is thicker and will stick to a spoon when dipped in. This apparently has more oil than most because it runs off the spoon. Hope that makes sense. Anyway, I'm looking for a recipe for this delicious Ranch dressing or one like it.
Thanks
Martha