Absolutely Fabulous Greek/House Dressing Recipe

This is the 'secret' greek dressing recipe from the pizzeria that i work at. The recipe makes almost a gallon but can be scaled down easily. It can be used for picnics and travels very well, since it doesn't need to be refrigerated. This is the best dressing i have ever tasted, people offer to buy it constantly, but if we sold it we wouldn't be able to make enough to use in the restaurant