A wood-burning oven is the newest must-have for the acquisitive cook

As restaurateurs know, just about any item that a menu describes as "from a wood-burning oven" is likely to sell out. The term promises something simple and rustic, charcoaled and deeply flavored, alluringly European but still intensely friendly. This is comfort food with an extra octave of flavor, as Wolfgang Puck demonstrated when he introduced the world to designer pizza at Spago in the early Eighties. Nothing speaks of hearth and of community like a dish of something lightly charred and smoky.

Perhaps that explains the growing popularity of wood-burning ovens for American homes. Mugnaini Imports, which in 1989 became the first U.S. company to focus solely on domestic-size wood-burning ovens, reports a 100 percent growth in sales for each of the past three years. The Texas-based Renato Specialty Products, long an industrial supplier, has seen similarly steep rises in annual sales every year since it began offering home models in 1986.

Predictably enough, the top states for wood-burning ovens are those with the best outdoor-living climates: California, Hawaii, Florida, Texas and Arizona. The Los Angeles-based supplier EarthStone, which sold about 100 of its smaller ovens to homeowners last year, reports a big Tennessee market among music-industry people. Fragrant smoke now curls from the patios of villas and beach houses in the Hamptons, along the Florida coast and in California's wine country. Their owners have been seduced by what Andrea Mugnaini, the CEO of Mugnaini Imports, picturesquely terms "the social magnetism of the wood-burning oven." Mugnaini herself became enthralled while visiting relatives in the Tuscan hills in search of wines and olive oils for her import business; she brought an oven home and liked it so much that, against all advice, she began importing them. Other owners may have been inspired by the well-known chefs who have bought models for their restaurants: Seen Lippert of Across the Street in Manhattan and, in the Bay Area, Maria Helm of PlumpJack, Paul Bertolli of Oliveto and Alice Waters of Chez Panisse.

The ovens themselves are not exorbitant in price. The Rolls Royce of the group, Mugnaini's Valoriani--hand-built to a design patented by Sylvio Valoriani a half-century ago--costs $2,750 for the Piccolo model and $3,150 for the larger Medio. The brick-walled Renato oven starts at $1,500; most models go for around $3,000. The steel-framed EarthStone kits run from $2,000 to $3,400.

Although Renato, EarthStone and Bravo (another Los Angeles supplier) offer what they call preassembled ovens, most models need to be installed by a professional mason. Shipping also has to be factored into the cost, not to mention fuel. Oven owners need a continuous supply of 12- to 20-inch lengths of hardwood--never resinous pine or spruce, which doesn't give off enough heat, but dry oak, maple (popular in the Midwest), fruitwoods like apple, almond, peach, cherry and grape, or (especially in Hawaii) mesquite.

The most important quality to look for in an oven is a capacity to retain heat evenly at high temperatures. A long-burning wood fire approaches 1,000 degrees Fahrenheit and will crack any material that, like concrete, retains pockets of moisture or cold. The best material for an oven is a high-fired alumina-rich clay, which spreads heat uniformly but is dense enough that it doesn't absorb any smells or residues. The Valoriani's refractory cotto clay, gathered from the hills of Reggello, near Florence, is predictably top of the line. Bravo uses an identical clay, and EarthStone's 80 percent alumina-content walls are similarly efficient, if less romantic.

Another consideration is customer support, and here too Mugnaini scores high. Her company's Web site (see "Resources," above) offers cooking tips, supplies recipes and includes an owners' club; Mugnaini herself gives oven lessons at her hilltop villa on the central California coast. Maurice Sabbagh of EarthStone conducts cooking seminars for potential customers in his Los Angeles showroom, and his company too has its own Web site (see "Resources").

As far as care and feeding go, a wood-burning oven is more of a challenge than a backyard grill, but the techniques are easy to master. Most makers recommend an initial curing--lighting small daily fires that get bigger and hotter over the course of a week--but after that the process is fairly straightforward. "This kind of cooking is slow, not labor-intensive," Mugnaini observes. "It's more art than science. It involves smell, touch and sight; you use your hands more."

Several specialized utensils come in handy: a five-foot-long palo per infornare, or "peel," for extracting red-hot dishes from the oven; a palino, or spatula, usually with a wooden handle, for rotating pizzas; and a brass spazzola, the only kind of brush for sweeping up the ashes that won't burn up or scratch the clay.

Those who balk at the idea of learning to cook all over again might do best with a Renato oven, which combines high-tech elements--a converter to gas fuel (usable on its own or in combination with wood), a temperature gauge and an ash collector--with the romance of wood smoke. But the very alteration in routine is what appeals to many of the people who purchase these ovens.

"This old-fashioned way of cooking has an amazing effect," Mugnaini says, pointing out that over the course of several hours various dishes can be seared, roasted or baked in the oven's decreasing heat. She might start with crisp-crusted Neapolitan pizza, which bakes in a flash on the oven's floor when it's at its hottest, and follow when the oven is slightly cooler with a roasting session of, say, chicken stuffed with oranges, garlic and herbs, accompanied by asparagus and potato gratin. Then she'll keep the flue closed all night to retain the heat and bake fresh bread the next morning for breakfast. Since nobody's salivary glands are immune to food like that, it's a good bet food "from a wood-burning oven" will be appearing on more and more home menus.

KATE SEKULES lives in New York City and writes about travel, food and boxing.