A chef attempting to source all his ingredients from inside London's M25 orbital motorway may sound like a joke, or a gimmick, but Oliver Rowe, head chef at the new Konstam at the Prince Albert in King's Cross, is taking this self-imposed challenge very seriously indeed.

However, Rowe, who already owns and runs the locally respected Konstam café in nearby King's Cross Road, insists that he is no eco-warrior. Rather, he is interested in taste. "If we can get produce that takes less fuel to get to us, but tastes great, is fresher and more nutritious, then fantastic," he says. "We are always being told to eat local food, and I wanted to see if this was realistic in London."

Restricting his sourcing options, though, does mean a lot more inventiveness and creativity, based on an awareness of the seasons. So, for instance, when rhubarb is around, Rowe will use it in as many dishes as possible - the most obvious being a good, old-fashioned, comfort-inducing, roasted rhubarb with custard (£5). "Things are joyously exciting when they are in season," he says. "And, most importantly, they taste good."

But Rowe is not only relying on suppliers. He is also growing produce on his allotment and aims to use every little bit of his crop. For example, chargrilled Amersham pork loin chop with spätzle and chervil dressing (£13.50) is served with cabbage tops. These are usually grouped under the "spring greens" label but they're tasty, classic British fare.

In fact, Rowe is mining British cuisine's history to find other dishes that work with local produce. "It's not about being original, it's about finding things that work here," he says.

So far, Chesham goats' cheese and nettle pirogi with breadcrumbs (£6.50) is his most popular starter, and Rowe thinks this is because many of the customers in his 70-seat restaurant remember nettle soup from some point in their childhood and decide to give it a go.

With a brigade of five, including himself, Rowe is not limiting himself to British cuisine, but mining the culinary traditions of northern Europe as well. This means he can also look through Polish, Finnish and Scandinavian history for dishes which work well with English produce. "We have pirogi because we can't have ravioli," he admitted. "But it shows that most food is interchangeable between countries."

Ox tongue is another ingredient Rowe wants to repopularise. His favourite dish to showcase it is seared ox tongue persillade and hawthorn salad (£6), for which he slow-cooks the tongue before slicing quite thickly and searing it. Then he adds the meat to the salad for tossing. Foraged forest food such as the hawthorn leaves - or hairy bitter cress, wild garlic and wild wood sorrel - give the dish a bit of a kick, not to mention a curiosity value.

Rowe is not pedantic about the local sourcing rule; when it's absolutely necessary, he will break it, but is always upfront about this on the menu. There's no getting around ingredients such as spices, lemons and coffee - they have to be imported, although Rowe's coffee is actually roasted in London.

However, he is hoping that his suppliers will let some of their fennel, coriander and celery go to seed for him so he can source at least some home-grown spices next year. The capers served in sauce form with his mutton chop and purple sprouting broccoli (£13.50) are also a cheat, but Rowe is working on a replacement ingredient.

It's certainly not easy for Rowe to keep within his self-imposed sourcing rules. Most of his suppliers are geared towards farmers' markets, which makes deliveries a bit of a headache. Yet, pulling off the local-sourcing challenge has its own rewards - and can be translated into extra revenue, too.

Take the restaurant's bread as an example: marketed as the Konstam London loaf, its wheat is grown in Barnet and Dartford, and milled in Ponders End, and the loaf itself is baked in Wandsworth. It is available not only as part of the restaurant experience but as an option for customers to buy and take home.

There's gold in that there former red-light district!

Chef's tip
We use rapeseed oil instead of olive oil. It comes from Epping and is sent to Suffolk for pressing. It is just as versatile but tastes quite different - much more nutty and woody.

What's on the menu

• Salad of raw beetroot and salted Canvey codfish with caraway and spring leaves, £6
• Devilled chicken livers on toast with hairy bitter cress, £6.50
• Cream of parsnip and bacon soup, £5
• Coq au vin with roast parsnips and bacon, £12
• Canvey Dover sole with spinach, wild garlic and beurre blanc, £15.50
• Ouefs en cocotte with creamed spinach and garlic mustard, wild wood sorrel and beetroot salad, £11
• Norbury blue cheese with London comb honey, £6
• Lavender ice-cream with honey snaps, £4
• Bread and butter pudding with Spanish lemon curd, £5

Konstam at the Prince Albert,
2 Acton Street, London WC1X 9NA. Click here for map
Tel: 020 7833 5040