A long time ago, before salad bars or diet books, before the first nutritionist had crawled out of the primordial tofu or the emaciated shadow of nouvelle had fallen across the land, there was, in the rural South such a thing as a balanced meal. The drinking part was an RC Cola, and the eating part was a Moon Pie. Five inches in diameter, bearing 350-plus calories, the Pie consisted of two cookies with marshmallow in between, the whole thing dipped in stick-to-your-gums chocolate.

The Moon Pie and RC regimen wasn't exactly dietetic (unless you counted the weight lost through tooth decay), but together they were lunch for generations of laborers—and barefoot 10-year-olds. Says Sam Campbell IV, the 28-year-old executive vice-president of the family-owned Chattanooga (Tenn.) Bakery, Moon Pie-maker to the world: "For a dime, an RC and a Moon Pie filled 'em up all day."

As the world changed and Southern laborers migrated northward, so too did the Moon Pie. The Chattanooga Bakery, where the first Moon Pie rose in 1917, now makes a million a week. The biggest markets are North Carolina and South Carolina, but the bakery ships to about 40 states. Only in Alaska, Hawaii and parts of the West are Pie people out of luck if they're seized with the craving.

Time, though, has taken its toll on the product. Moon Pies are just four inches in diameter now and sell for as much as 75 cents, a far cry from the original nickel. To compensate, the bakery has made most Pies double-deckers. And Campbell offers some gourmet tips. Proud heir to a Southern tradition, he makes it a point—strictly because it's his job, you understand—to eat a Moon Pie every now and then. But he disdains the old-fashioned approach of simply unwrapping the Pie and wolfing it down. No, Campbell likes to microwave his Moon Pie for about 20 seconds, then top it off with a dollop of ice cream.

Seventy percent of all Moon Pies are chocolate-covered, the rest being vanilla and banana. Anxious not to let time pass it by, the Chattanooga Bakery is experimenting with new flavors and may test a peanut-butter Moon Pie next year. So far no one has asked for a kiwi, goat cheese or radicchio Moon Pie. After all, not even a yuppie with a ravenous sweet tooth would want to get marshmallow all over his Audi.