"Here, touch my neck," is not something I usually hear in an interview, even one about skincare. But Tiffany Masterson is selling what she says is the secret to good skin, so she's basically wearing the product. And it works: she drops her age with the casual confidence of a woman who knows she looks damn good.

The product? An unassuming tan bar called the Wonderbar. Masterson was tipped off about the product by her brother and sister-in-law in Austin, who are partners in the company. "It first came out in Malaysia, and college students discovered it helped with their acne, and then it just exploded," says Masterson. "And over there, they want a product that does everything. They'll use it as shampoo too to get rid of dandruff. Men will shave with it."

Whatever you do, don't call the Wonderbar a soap. It's made of detoxifying, Heilmoor clay (said to contain over 700 healing herbs) and an algae complex called Chlorey’nahre. According to Masterson, "It's actually the same clay people have been using on their face in Europe for thousands of years," combined with a new binding agent that doesn't alter the pH, so it can be converted to a bar.

Masterson says she first tried the product about a year ago and noticed an immediate difference in her skin. "I did go through the healing crisis,"—that's what she calls the initial period of dryness and breakouts that can occur when Wonderbar first meets damaged or unbalanced skin—"but then I noticed a difference in my skin immediately." Masterson had friends asking for her secret, and started out with a $1,000 shipment. "I sold out in two hours," Masterson says.

Now selling at Kuhl-Linscomb and Austin's Perri Berri, Wonderbar has steadily gained followers both in Houston and beyond. In the fan club: the head of an exclusive Aspen spa and the beauty director at Harper's Bazaar, who included Wonderbar in the March issue as one of nine skin secrets. And Masterson foresees bigger things to come. "You can see in the orders, how there will be a wave after some kind of publicity, and those are people ordering the small bar, and then two months later, there'll be another wave—this time for orders of the large bar or the four-bar package. I feel like I've got a tiger by the tail."

It's true that Wonderbar could change the way people think about skincare. Forget the endless foams, cleansers, toners, emulsions, scrubs, and specialty serums on the shelves—the Wonderbar is specifically designed to be used alone, twice a day, with only moisturizer to follow.

"People can get hung up on the price, but I defy anyone to walk into a grocery store and buy a half-decent cleanser, toner, exfoliant and masque for under $40. Before Wonderbar I was using one of the most expensive skin care brands, and I was still walking into Sephora and asking, 'What do you have for dark circles? How can I fix my large pores?'" says Masterson.

From what I can see, Masterson isn't looking for skin solutions any more—she's found hers.

Wonderbar is available at Kuhl-Linscomb and at wonderbarusa.com. 25g bar, $40; 80g bar $105.