Image caption Marilena Zachou making tabbouleh in her kitchen

The traditional way of getting dinner is buy food and cook it, or to go to a restaurant. But what if someone in a nearby street has cooked more than they need and is ready to share it for a small fee? It's already happening in the Greek capital and will soon be starting in London.

It's time for Marilena Zachou to get up, make a Greek coffee, get the kids fed and off to school. And when the peace and quiet descends at 10am, the cooking begins. Today it is moussaka.

She gently fries the onion and minced lamb in olive oil. She reaches for the pepper, salt, paprika and tomatoes and inhales as the aroma fills the kitchen and escapes from the windows and out into the street.

She uploads details of the dish and watches the screen as people from the area order their portions.

There will be no wasted food in her household today. At least five other people in the Athens district of Marousi will be sharing her family's evening meal. By midday the entire oven dish has been sold. She notes down the delivery addresses for later.

This morning ritual is not unique to Zachou. It is happening across Athens.

Image caption Foteini Mangana, another Cookisto cook, and her spinach pie

Office workers, students and busy parents are connecting online with local cooks - anybody who loves cooking and can do it well - who provide them with a meal for less than they would be likely to pay anywhere else. In Athens, the price is usually between three and four euros (£2.50 to £3.40).

These sites generate the social glue of trust between strangers Rachel Botsman, Author

"I just could never calculate the correct portion amounts for my family," Zachou says. "We don't have a dog or a cat. I was throwing away so much. I guess making too much food is embedded in my Greek genes."

That was what led her to Cookisto, an online community of amateur cooks and hungry city dwellers.

She is now a Cookista, with a profile on the Cookisto website, and her meals are rated every day. Apparently her moussaka has "no excess oil, is always made with the highest quality products, and tastes just perfect". She is, according to those who eat her food, not just a housewife, but a five-star chef.

The site has attracted 12,000 cooks in Athens in the last few months. What began as a master's degree thesis (in the form of a business plan) for entrepreneurship student Michalis Gkontas has now become a reality in crisis-stricken Greece, and is due to launch in London next month.

Image caption Cooks with dishes available at time of writing

"It is a win-win situation," says the 26-year-old Gkontas. "The cooks get to earn a little extra, while foodies get nutritious home-cooked dishes for cheaper than if they were to get a takeaway."

He is one of many young Greeks turning to the start-up scene following the rise of unemployment to a staggering 27.9%, and the rapid shrinkage of the once-bloated public sector - long the natural choice for many graduates.

For Zachou, the extra money she makes from Cookisto, about 200 euros (£168) a month, goes towards the supermarket shop.

"It's not all about the money," she says. "I feel we are pulling together in the crisis. Many students are struggling to make ends meet. I've been there… fed up of eating bread and takeaways. It's nice I can provide them with food their mothers would cook and for very little."

It's all part of what Sydney-based innovation consultant Rachel Botsman calls the "revolution" of collaborative consumption, or the sharing economy. Since the global financial meltdown, "people have reverted to old market behaviours that involve trust - swapping, sharing, renting, bartering", she says.

What is collaborative consumption? Renting, lending and even sharing goods instead of buying them, says Time magazine. "You can see it in the rise of big businesses like Zipcar, which gives members the chance to share cars part-time... or Airbnb, which allows people to rent their homes to travellers. "But the real benefit of collaborative consumption turns out to be social. In an era when families are scattered and we may not know the people down the street, sharing things - even with strangers we've just met online - allows us to make meaningful connections."

Cookisto joins the likes of Airbnb (bed and breakfast), Lyft (ride-sharing), Liquidspace (space rental) and Taskrabbit (deliveries and errands) - all occupiers of this online space where trust and online credibility is crucial to success. The reviews say it all.

"It's what monkeys are born and bred to do, share and co-operate," Botsman says. "These sites generate the social glue of trust between strangers. Ultimately, a shift is happening from institutional trust to peer trust."

Office worker Dimitris Coustas buys at least one lunch from Cookisto most weeks.

"The cooks deliver the dishes to you themselves," he says. "Sometimes they add a free dessert to encourage you to choose them again next time. It's funny, sometimes the housewives will ask if you have ordered from anyone else on the site and enquire how their food rates compared to others'. I think there is quite a bit of competition!"

Image caption Dimitris Coustas (in white and grey T-shirt) and friends

Cookisto has no way of monitoring the hygiene of the cooks' kitchens or checking the freshness of ingredients, but it urges users to post truthful reviews.

Marilena's moussaka 1kg aubergines

three or four potatoes

600g minced meat

vegetable stock

three or four ripe tomatoes, chopped, or 1/2 cup of tomato sauce

two medium onions, chopped

1/2 cup olive oil

salt, pepper and paprika

grated cheese Slice the aubergines, salt well and leave to stand for 30 minutes. Rinse well and dry with kitchen roll. Preheat the oven to about 180C. Put the sliced aubergines and potatoes on a non-stick tray, brush with olive oil and bake for 20-30 minutes until brown. Fry the onion and meat in olive oil until brown. Add pepper, salt, paprika, tomatoes and stock and simmer for about 20 minutes. Make a white sauce by combining 100g flour, 100g butter, 1 litre milk, salt and nutmeg. Layer the aubergines and potatoes in a baking dish, then add the meat. Sprinkle over cheese and then pour the milk mixture on top. Bake at 180C for 35 minutes or until the top browns. Greek recipes and helpful tips from BBC Food Red lentil and aubergine moussaka More moussaka recipes from BBC chefs

"At first it felt a little dodgy, ordering food from someone you don't know," says Coustas. "You think, 'Who are they? Who is this? What will it taste like? What if it makes me ill?' There is huge trust involved."

In Greece, the Cookisto community has spread outside the internet realm, with users organising get-togethers and feedback sessions. Evangelia Tavladoraki, a political scientist by training, says being part of that community has helped her gain new confidence after the shock of unemployment.

"Every day I feel proud helping others. And the best reward I can get is when people tell me how much they like my food," she says. "This is another road I have gone down because of the crisis. I didn't study cookery. But it makes me feel optimistic."

She is even considering opening her own business. Her marinated sweet and sour chicken sells out in minutes, which appears to indicate that demand for ethnic food in Athens outstrips supply.

Exactly which dishes make Londoners' mouths water will become clear in the next few weeks when Cookisto makes its first foray into the UK. Perhaps they will order from the ex-lawyer, who has a YouTube cooking channel, the Italian stay-at-home mum, or the recent history graduate who followed up her studies with classes at Le Cordon Bleu.

Currently one of the nearest dishes online is 2,134km away in Athens - stuffed peppers and rice by Efi.

Although Gkontas says he came up with Cookisto "to solve his greatest daily problem - access to delicious homemade food", Nikki Finnemore, who is handling the UK launch, is keen to emphasise that this peer-to-peer marketplace is about more than lunch or dinner.

"Just like Airbnb is not just about accommodation, but about friendship, Cookisto is not just about food but about coming together as a local community and sharing the fruits of your labour, your creation," she says.

"It's the experience of trusting a relative stranger to make a meal for you and to then meet for a face-to-face exchange."

You can follow the Magazine on Twitter and on Facebook