McDonald's is adding a new dipping sauce to its lineup-but only for a limited time. Source: McDonald's As we make our way toward the final days of summer, McDonald's is serving up a special way to savor the golden moments of the season with their new, limited-edition sauce. Starting Sept. 3, McDonald's is introducing a new Special Edition Gold Sauce: a harmonious blend of vinegary North Carolina BBQ sauce infused with notes of honey, smoke and mustard, made to pair perfectly with its crispy chicken.