Bartender Abigail Smith of Big Bar in Los Angeles doesn't recall what possessed her to create a cocktail with red onion. "I suppose I'm just always looking to outdo my own weird," she says. "So I tried making red onion syrup, and it turned out really well." When she cooked and salted the onions, she discovered that they lost their polarizing bite. The syrup put a complex and savory spin on this Margarita-inspired cocktail.