This ridiculously-good baked cheese dip is one of test kitchen chef Karen Rankin’s all-time favorite dishes to bring to parties and tailgates. It’s the ultimate oozy-gooey cheese appetizer. As Rankin puts it, the way Swiss cheese, savory bacon, and sweet caramelized onions play together is nothing short of divine. Cream cheese and mayo contribute a necessary touch of creaminess, while scallions and fresh thyme offer a added savory flavor intrigue, and a finishing touch of crispy onions on top delivers a pleasant crunch. Serve with pretzel rods, or other dippers of your choosing, and plan on handing the recipe over to anyone who tries it. Trust us, they’re gonna ask.