Taste of the great outdoors: No foodie's garden is complete without a wood-fired pizza oven

Gwyneth Paltrow and Jamie Oliver both have one; Guy Ritchie can't stop talking about his. Rob Sharp discovers what makes them so hot

You grab a cloth to pull open a salmon-coloured ceramic door, and are greeted with the smoky smell of toasted dough and sizzling cheese. Leaning down, you pull out a baking tray holding succulent pork loins, leave it to rest to one side, and turn to remove two pizzas with crisp bases and molten toppings from the sexy new appliance you have purchased for your garden.

Wood-fired pizza ovens are not just physically sizzling hot – they are also more popular than ever. Andrew Manciocchi, the co-founder of Orchard Ovens, the UK distributor of Valoriani, one of the most prestigious pizza oven brands in the world – says in 2008 his orders were up 300 per cent on the previous year. So far in 2009, he claims, sales are even higher. Manciocchi's success has been sparked by his ovens' massive appeal to those in the public eye. Jamie Oliver used one of his ovens in his television series Jamie at Home, which, when it was screened last February on Channel 4, attracted 2.5 million viewers. Gwyneth Paltrow has even taken a break from her notoriously strict macrobiotic diet to buy some of this bespoke culinary kit. "We have a wood burning pizza oven in our [London] garden," she told the celebrity magazine People last September. "I'm using the oven a lot – you can cook anything in there, it's amazing." What's more, when Guy Ritchie was interviewed by an American celebrity reporter in January about his divorce from Madonna, the director chose to talk mainly about his favourite wood-fired garden appliance (no prizes for guessing which one). So what is the appeal?

"They are a great alternative to barbecuing," says Theo Randall, head chef of Theo Randall at London's InterContinental Park Lane in Mayfair. "They possess this incredible residual heat. You can use them for everything from roasting shoulders of lamb to making bread and vegetables, and they look nice in the garden, too." The ovens can be used to rustle up smoke-finished dishes of everything from roast pork, fish, stews, bread, bread and butter pudding or rhubarb crumble.

However, despite the ovens' association with the rich and famous, they will not break the bank. You can opt for a variety of sizes, some kinder on the wallet. These range from those just big enough to rustle up a 12-inch pizza (which might cost a few hundred pounds) to the larger one-metre models beloved of the Hollywood elite (these can set you back up to £3,000). Operating them is simple – you just light a fire inside using conventional firelighters, let the interior heat up, then extinguish the fire and wipe away the embers. Insert your food directly on to the stone base and cook to taste. Randall – who creates bespoke pizzas for Pizza Express – says the ovens are perfect for conjouring up a crisp-based pizza. "It is the way pizzas are supposed to be made," he says. The hot stone base can also be used to sear meat to give it a beautifully moisture-rich finish.

Variations of the modern day wood-fired pizza oven have been used for hundreds of years in different countries. Its cousin, the masonry oven, has been used in the Persian Gulf for centuries to cook khubz (flatbread). In India, they are called tandoors. Valoriani has been making its ovens in the hills of Tuscany since 1890. The company has its own mine, and has made 250,000 pre-fabricated wood-burning ovens since the 1940s.

Manciocchi says he started selling the ovens in Britain in 2003 because he could not buy a wood-burning oven in the UK, and had been trying for several years, until he happened upon Valoriani's operation in Reggello while on holiday. When he secured the exclusive contract to supply their goods in Britain he approached his local bank manager and took out a loan. He says his bank manager was one of his first customers.

"It's a lovely old wood oven," says Oliver, talking on jamieoliver.com. "I've done a lot of cooking in it. I think it's got fashionable because it's outside, it's sociable, food tastes better in it. I love cooking in it. It's the old fashioned way. I think if you master the personality of looking after coal or wood in one of these naturally you become more sensitive to cooking. You don't just turn it on, you are connected to it more. There's something Medieval about it. Mine was a couple of grand of work after the initial kit, but I've seen them have all sorts of finishes, built into the sides of sheds. You can get an oven for a boat or install it into your kitchen."

"The thing is, wood-fired ovens are Jamie's thing," explains Manciocchi. "I got approached a couple of years ago by a local celebrity chef, Paul Heathcote [head chef of the Longridge restaurant in Preston] and he said he wanted to use our name. It was a deal we couldn't afford and I jokingly said I needed to do a deal with Jamie Oliver to make it worth it. Three weeks later I got a call from Jamie's people. I couldn't believe it. He had been put in touch with me through my Italian contacts, and they were being loyal to me."

Pizza ovens are going to become more readily available as they become more fashionable. "You can now get small ones of various sizes that come off the shelf," continues Randall. "You just plonk them on to a sturdy table and can buy them for around £300. They last for ever. I have seen smaller ones for less than that, though they have got to be reasonable to size to put anything inside." A variety of books on building a cheaper kit oven are available online, though Manciocchi is predictably scathing about their effectiveness. Either way, a pizza oven is set to be the must-have accessory for your garden over the coming year. "I said to my business partner Matt Draper in December that we need a bit of a kick-start with the recession coming on," concludes Manciocchi, who supplied both Oliver and Paltrow's ovens. "But since then the market has just grown and grown. I think now, after the initial boost from the celebrity factor, it's the factor of, well, if my friend has got one then I want one."

Perfect pizza: How to use your oven

* Centuries old, even early civilisations realised the fantastic appeal of taking food from the field to the fire, and it's this simplicity and the sensational taste results that account for the popularity of outdoor ovens today.

* A traditional wood-burning pizza oven is made out of clay and refractory concrete bricks, a heat-resistant mix that can withstand high levels of heat.

* A wood burning-oven will generally take around an hour to an hour and a half to heat up.

* A fire is lit inside with the chimney and door open, allowing the gasses from the wood and the smoke to exit. When the fire is lit, the interior of the oven retains the heat and the oven should be allowed to get white hot. Then the fire is allowed to die down.

* The heat is spread around the oven by radiation, and all the fire's heat that has been absorbed by the oven walls, slowly spreads out around the oven.

* The oven will have a slightly higher temperatures in the ceiling than the floor, due to convection current.

* Once the embers are swept to one side, the door and chimney should be closed. At this point, the oven is perfect for cooking foods that need a very high temperature, as it's around 800°F or 425°C. This is the optimum time to put in thin-based pizzas and they'll cook in around 90 seconds, leaving you with the traditional crispy base.

* When the temperature has dropped to around 450°F or 230°C, this is the time to put in big roasts or joints of meat. It's perfect for slow-cooking meat so that it falls off the bone and it gives it an incredible smoky flavour.

* How long the oven stays hot depends on how insulated the walls are. As an average, walls that are 4in thick should be able to cook at a high heat for about six hours.

* Once the oven drops in heat, it's great for slow-drying fruits, vegetables and herbs.

* And the best bit? There's no cleaning needed. Any grease left in the oven simply burns off in the heat.

Laura Martin