Mix all of the ingredients in a small bowl. Cover and refrigerate for an hour, at least, before serving.
To Make The Big Macs
Lightly toast two bottom buns.
Season the hamburger patties with salt and pepper, to taste. In a medium sized skillet, cook 1-3 minutes on each side, or until cooked through.
On the first of the two bottom buns, add ½ tablespoon of the Special Sauce, ½ teaspoon of the onion, ⅛ cup of shredded lettuce, cheese, and one hamburger patty.
Place the other bottom bun on top, and top it with the same items mentioned above, but no cheese. Top with the remaining bun top.
Notes
This recipe, for simplicity's sake, is written to prepare one Big Mac. Double, triple, and so on until you've made as many as needed.