I'll normally make them with Mayo, Mustard, and Vinegar as the main ingredients. I never use specific measurements. I'll usually just combine the ingredients until it tastes right. The vinegar adds a nice tangy flavor, and it's usually a pretty solid filling.
Today they served some at the DFAC (Dining Facility), and it was very evident that they had used a liberal amount of onion and garlic powder and I could taste no vinegar. The filling was very... airy? Like it had no substance.
It was quite differant from what I'm used to, but I really enjoyed it.
So how do you guys do it?