It is a beloved Jewish dish, served at Shabbat dinners to family and friends and reputed to have powerful medicinal properties. It is not normally cooked or served in a mosque.

But on Sunday, vast quantities of chicken soup – often known as “Jewish penicillin” – were being made at the East London mosque by Jewish and Muslim volunteers to be distributed to homeless centres.

Mounds of carrots, garlic, onions and celery were peeled and chopped on long benches by Muslim scouts, volunteers from Muslim Aid, members of the B’nai B’rith Youth Organisation and the New Stoke Newington Shul.

At another table, LSE student Emily Otvos instructed fellow students on the preparation of matzo balls, the traditional dumpling served with chicken soup – despite confessing that she usually left them on the side.

Tahir Iqbal, events director of Elite Caterers, was in charge of preparing 90 halal chickens for the pot. His company, which caters for Asian weddings and corporate events, donated the ingredients, equipment and transport for the cookathon.

“This is a new experience for us. I’ve never made Jewish chicken soup before, but I’ve been practising for two weeks, including on my family,” he said. The nearest Asian equivalent was chicken yakhni, a spicy broth, he added.

Across the UK, more than 2,500 servings of soup – kosher, halal, vegetarian and vegan – were being cooked at 20 venues, with soup-making events also taking place in Germany, Poland, South Africa and Australia, as part of Mitzvah Day – a day of social action led by the Jewish community but involving people of other faiths and no faith.

Traditional Jewish chicken soup contains dumplings known as matzo balls Photograph: Sarah Lee/Guardian

Other activities undertaken by more than 40,000 volunteers around the world included hosting tea parties for refugees, collecting and sorting clothes and food for those in need, cleaning up cemeteries and parks, and visiting care homes.

At East London mosque, 900 servings of chicken soup and more than 100 portions of vegetarian (spinach, walnut and yoghurt) soup were being delivered to projects run by the Salvation Army, St Mungo’s and the Acre Lane Centre, based in Brixton, south London.

“Chicken soup is the Jewish food of choice,” said Laura Marks, the founder and chair of Mitzvah Day. “As well as its famed medicinal properties, it has all sorts of emotional properties – friendship, family, togetherness, love, nurture – they’re all in that bowl.”

There was a common perception that Jews and Muslims did not get on, she said. “But Mitzvah Day is about the common values that underlie both religions – the commitment to social action and social justice. We are both commanded by our faith to do good deeds and contribute to society. Most of the Jews here today won’t have been in a mosque before, and most Muslims won’t have Jewish friends. But here we are, chopping vegetables together.”

‘Mitzvah Day is about the common values that underlie both religions.’ Photograph: Yakir Zur

The East London mosque is one of the largest in Europe, and serves the UK’s biggest Muslim community. Until three years ago, there was a tiny synagogue next door, a remnant of the once-thriving Jewish community of the east end. It closed and was sold to the mosque.

Jehangir Malik, the chief executive of Muslim Aid, which teamed up with Mitzvah Day for the event, said that in the 1930s the area would have been full of Jews. The chicken soup cookathon was “a wonderful initiative to bring our two communities together in a part of London which is meaningful to both of us and to spread a positive interfaith message around the world”.

At 12.30pm, as cooked chicken was being shredded for the first batch of soup, the Muslim call to prayer rang out. “Food brings us together,” said Marks.