The Happiest Hour

The Happiest Hour burger manages to combine the best of both In-N-Out Burger and Shake Shack. Two beef patties, American cheese, lettuce, tomato, pickles, confit onions, and a special sauce that’s similar to Russian dressing — only with mustard to temper the sweetness — are stacked on a potato bun. It’s a messy endeavor, and be prepared to brave a loud space.