When Minneapolis donut chef Teresa Fox heard that Huy Fong Foods Inc., maker of Sriracha Asian-style hot sauce, might be forced to shut its factory near Los Angeles, she knew she needed to stock up.

The co-owner of Glam Doll Donuts, a hip bakery popular with a late-night crowd, uses the sweet and spicy chili sauce in the icing for her peanut butter and Sriracha-flavored "Chart Topper" doughnut. To ensure she would have enough on hand, Ms. Fox said she purchased five extra cases of Sriracha, each with a dozen 28-ounce...