ROSEMEAD, Calif.

AFTER-HOURS calls to Huy Fong Foods, here in the suburbs of the San Gabriel Valley east of Los Angeles, are intercepted by an answering machine. One recent day, 14 messages were blinking when Donna Lam, the operations manager, hit “play.”

A woman told of smearing Huy Fong’s flagship product, Tuong Ot Sriracha (Sriracha Chili Sauce), on multigrain snack chips. A man proclaimed the purée of fresh red jalapeños, garlic powder, sugar, salt and vinegar to be “the bomb,” and thanked Ms. Lam’s employers for “much joy and pleasure.”

Another caller, hampered by a slight slur, botched the pronunciation of the product name before asking whether discount pricing might be available. Finally, he blurted, “I love rooster sauce!” (A strutting rooster, gleaming white against a backdrop of the bright red sauce, dominates Huy Fong’s trademark green-capped clear plastic squeeze bottles.)

“I guess it goes with alcohol,” deadpanned Ms. Lam, who, like David Tran, the 64-year-old founder of Huy Fong and creator of its sauce, is both proud of the product’s popularity and flummoxed by fans’ devotion.