The key to recreating the Big Mac is obviously perfecting the sauce. Some say it’s simply Thousand Island, but the clever folks at McDonald's deserve much more credit for this masterpiece we crave.
In order to recreate the sauce, I had to ensure that I had a supply that I could taste on its own — away from the other great flavors this burger stacks. So I requested "extra on the side." The friendly woman behind the counter didn’t flinch. She quickly produced a sundae cup half-filled with the neon-salmon-colored sauce. When I took a big sniff, all I could smell was a chemicalesque aroma. Tasting, on the other hand, yielded that wonderful flavor. Several tastings and I was convinced. The secret ingredient? Mustard. Simple yellow mustard. Add that and a pinch of sugar to a Thousand Island-style sauce, and you’ll be surprised how closely it resembles the real deal.
Note: It’s easy to throw together a Big Mac-like burger in minutes once you have the sauce made. So to save time, make a big batch of the sauce, omitting the onions (they are the only ingredient that will spoil quickly). Refrigerate the sauce in a plastic container for up to 1 month. When you’re ready to enjoy a burger, simply add the correct quantity of onion to the amount of sauce you’re using.
Even better: Save time and calories by omitting the second bun bottom and simply make one patty instead of two with the three ounces of beef. This way, you’ll need only 1 ½ tablespoons of sauce. You’ll be left with a more nutritionally balanced burger. Plus, you’ll still have room for some fries or a side salad, all the while still enjoying that great Big Mac flavor… in minutes.
In a small bowl, combine the mayonnaise, relish, ketchup, sugar, and mustard. Stir to blend well. Cover and refrigerate for up to 1 month. Stir in the onion just before serving.
Divide the beef in half. On a sheet of waxed paper, shape each half into a 4-inch patty. Season both sides with the salt. Transfer the waxed paper to a plate. Place, uncovered, in the freezer for 5 minutes.
Preheat a large nonstick skillet over medium-high heat until drops of water sizzle when splashed on the pan. Place the patties in the pan. Cook until no longer pink, 1-2 minutes per side.
Meanwhile, place the bun top and bottoms, cut sides down, in the pan. Cook until toasted, about 1 minute. (If the pan is not large enough to hold the patties and the buns, first cook one of the patties with the bottom bun and then start assembling the sandwich while the others cook.) Just before the patties are cooked, place the cheese on one of the patties.
Place one of the bun bottoms on a plate. Spread on 1 tablespoon of the sauce. Place the cheeseburger, cheese side down, on the bun. Spread 1 teaspoon of the sauce on the second bun bottom and place, sauce side down, on the cheeseburger. Top with the remaining sauce, the onion, lettuce, pickles, the remaining burger, and the bun top.