Bryn Williams is looking for a new butter. The chef is fussy – it must be the right consistency, quality and size. And it has to be Welsh. "I never use Welsh produce just for the sake of it. It must be top-quality, but I take inspiration from food I was brought up on. I used to watch my grandmother churn her own butter and pour buttermilk over crushed new potatoes. Fantastic."

Williams has long been banging the drum for Welsh food, serving up the finest produce from the valleys at his acclaimed London restaurant Odette's. Now, he has company – Wales is ready to be noticed, with a government-funded True Taste of Wales brand and a flurry of gastro-inspired initiatives. True, Wales has always been respected in food circles, chiefly for its renowned Abergavenny food festival, but now there is a concerted effort to put the country firmly on the global food map.

A touring kitchen showcasing Welsh food at festivals is going global, with visits to Singapore, Barcelona, Paris, Cologne, Shanghai, Washington and Dubai. Gastro-tourism is growing, with young companies such as Snowdonia Safari taking visitors to sample local produce at homegrown businesses – think stewy cawl and Welsh cakes – and Turnstone Tours taking tourists to people's houses for home cooking.

And it is paying off, with companies reporting increased business. "One beer company's exports have grown from 5% to 17% in the past three years," says Nerys Howell, True Taste food consultant. Wales is also listed as one of the top three destinations for gastro-tourism, according to the journal Rural Geographies. "People are discovering how good their produce is," says Shaun Hill, from Michelin-starred The Walnut Tree, near Abergavenny. "We have first-class lamb, good beef, game, cheese and some very good charcuterie such as Trealy Farm's. Wales has always been a poor country so the culture is simple food – baking, and good meat or fish."

Ah, the produce, testament to Wales's grassy slopes, mountainous farmland and, as Williams says, the fact that "it never stops bloody raining". Speak to most chefs in Wales about the country's produce and their eyes grow dewy. "The coastline is fabulous," says Stephen Terry, from The Hardwick, Abergavenny. "Great crab and lobsters, fantastic Welsh samphire, salt-marsh lamb and cheese. Perl wen kicks the ass off brie."

There is a strong spirit of localism. "Research shows that 80% of visitors are looking for a Welsh food experience," says Howell. Elisabeth Luard, author of A Cook's Year in a Welsh Farmhouse, points out an interesting mix: "Incomers are keen on green self-sufficiency; locals, who lived isolated lives on the mountains, have a tradition of necessity." Most people bake, she says, many own pigs and chickens, and she used to get home-churned butter from her neighbours.

So what are chefs rustling up? Terry does a Welsh rarebit made with pressed ham hocks, acclaimed Hafod cheese and Welsh beer ("there's a brewery in virtually every valley"), Black Mountains Smokery smoked salmon with laverbread (made from seaweed) and rye bread from nearby award-winning baker Alex Gooch. Back at Odette's, Williams does a light bara brith ("speckled bread"), a Welsh cheeseboard – perl las, caerphilly and perl wen – with Welsh buttermilk soda bread and panna cotta. Then there's Welsh black beef, pedigree Welsh pork and mutton – and, of course, slow-roasted Welsh lamb (new season and salt marsh)."They would kill me at home if I didn't!"

For Williams, who has staked his reputation on bigging-up Welsh food, its growing clout is vindication. "I'm known as a chef who uses Welsh ingredients," he says, "It took years to gain the confidence to stick it on the menu. Welsh food isn't well-known, people found it strange, but Welsh produce can easily compete with [that of] anywhere else in the world."