<P> The name was popularized by a 1974 advertising campaign featuring a list of the ingredients in a Big Mac: "Two all - beef patties, special sauce, lettuce, cheese, pickles, onions--on a sesame seed bun ." </P> <P> Big Mac Sauce is delivered to McDonald's restaurants in sealed canisters designed by Sealright, from which it is meant to be directly dispensed using a special calibrated "sauce gun" that dispenses a specified amount of the sauce for each pull of the trigger . Its design is similar to a caulking gun . </P> <P> In 2012, McDonald's admitted that "the special sauce ingredients were not really a secret" because the recipe had been available online "for years". It consists of store - bought mayonnaise, sweet pickle relish and yellow mustard whisked together with vinegar, garlic powder, onion powder and paprika . </P> <P> The Big Mac, along with many other McDonald's products, was first served in a "clamshell" styrofoam container that was phased out beginning in 1990 due to environmental concerns . The product is now sold in a collapsible cardboard box . </P>

What is mcdonald's special sauce on the big mac