Skiers swear by it. Many backpackers wouldn't leave home without it. And it just might be the best news since the electric blanket for America's estimated 27 million sufferers from chronic cold feet. It is called WarmFeet, and it is a mixture of herbs and spices including ginger, capsicum (cayenne pepper) and bassica (a blend of two different mustard seeds). Sprinkled in powder form inside socks, it is putting the tingle back into frosty toes.

Creator of this concoction is Samantha Stevens, 41, an outdoors-loving, transplanted Englishwoman. After a trial-and-error marathon in her kitchen in Aspen, Colo., she came up with the formula of natural ingredients that would keep her feet toasty on the ski slopes. Says Stevens, "I finally got what I wanted: the warmth that comes on within an hour, then flattens out and stays for a long time."

Stevens admits her herbal mixture is no guarantee against frostbite and says she does not know how her feel-good formula works, except that it causes the smaller veins and capillaries in the feet to dilate and provide more warming blood. But Divajex, the California firm that's marketing the small packets ($2 for a weekend trial size; $9 for a 14-day supply) is so impressed it's offering a money-back guarantee. Stevens advises that cool water be used to wash the powder off, since a leap into a hot tub might cause eye-bugging hotfoot. And, she adds, keep the powder, which has a slight musty scent, away from mittens, which could carry the irritants to the eyes.

Born in London, Stevens says she first came to the U.S. in 1965 "following a man," had a brief career as a fashion model, then a fling at TV acting. In 1975 she moved to remote Lasqueti Island, off Vancouver. Afflicted with back pain doctors couldn't cure, she tried a friend's herbal remedy. When it worked, Stevens was sold on herbs.

"WarmFeet makes people happy—they just walk around comfortably," says Stevens, who now lives in Malibu. Among her converts is Minnesota Vikings placekicker Benny Ricardo, who used WarmFeet last season, and now endorses it. "I felt like my body was in Alaska," he says, "and my feet were in Southern California."