When the group was set up in 2011 Facebook was a slightly different beast. "People weren't really on Facebook," Sara recalls, "but suddenly it took off and now it has changed people's Pesachs - the Pesach Recipes group has 6,065 members. The recipes are really exciting. Even before Purim is over people are talking about what they're going to make for Seder."
Meanwhile the Shabbat group, which has 5,951 members and counting, is "used daily. People are always commenting, putting up recipes and pictures," she says.
Sara, 38, who worked for the JNF and as a press officer for the Chief Rabbi's Office under Jonathan Sacks, is originally from the UK, living in Leeds, Manchester and Essex before making aaliyah five years ago. So it is perhaps not surprising that the group has a mixture of Britons and Israelis. However, it has spread beyond Sara's immediate friends, with members from America, Europe and beyond. "It grows every day. Every time I look at my phone there's 20 people waiting to join."
According to Sara the site is mainly used by women with the occasional comment from men, and is a combination of requests for recipes, unsolicited tips or people posting their own beloved recipes. "Every so often someone will say 'I want to change my chicken soup recipe'. There will be hundreds of responses. It's amazing."
But why use the group rather than searching for a recipe online that, surely, is more precise?
"The group has much more of a human touch; I am not just grappling for an idea through a machine," says Ruth Isaacs-Holzer from South Bend, Indiana. "Also, these recipes have had success in the past."
Emily, from Borehamwood, agrees: "I do sometimes Google instead, but this way you get tried and tested recipes and useful tips." Emily thinks this is the group's strong point, "to get new ideas for something interesting to make, especially when entertaining".
Another benefit, Ruth adds, is that, as the membership is so global and diverse, if you have a question "it's not night-time, Shabbas or Yom Tov somewhere else in the world, so someone can always help out with an answer."
I tested out the group to ask members which recipe they'd found to be their new kitchen staple. Challah, strawberry sorbet, fake duck pancakes ("People rave about these," says Sara) and a Graham cracker tart with an Oreo filling topped the list.
But beyond the food, one of the main draws of the group seems to be a sense of community.
Ruth says that "some of the best tips/recipes have come from the online friendships I've established while being a member of this group", a sentiment that Tamara Koppel Russell, from Ra'anana, echoes: "It feels like an extended circle of friends, and is quite chatty."
Tamara uses the group to keep tabs on new cooking trends and post her own recipes. "I love the group as all recipes are kosher and relevant," she says.
Two of her most popular recipes - demonstrated by the impressive pictures she posts - include a Chanukia-shaped challah with fried onions (pictured above) "which got lots of likes" and a parev, nut-free, chocolate bar cake that she made for a school party.
And the thing that makes the group so successful, as Emily points out, is its reciprocal nature: "It's nice to share a good recipe with others who are looking."
As well as current members adding their friends or news of the group travelling by word of mouth (and full stomachs), Sara gets membership requests from chefs all over the world. "I don't accept them unless they want to post something very interesting or with a kosher angle; the group is for amateurs."
However, one very active member is Shlomo Klein, COO of American magazine Joy Of Kosher, who uses it in his professional capacity, to promote the publication and to increase brand awareness and traffic to the website. He says: "I personally enjoy the conversations on the group and interesting threads and perspectives brought out in them." He has noticed that "challah is one item that, no matter how different or how many times it has been posted, always gets people interested".
I speak to Sara Curtis on a Friday, so can't resist seeing if she puts her money where her mouth is. What is she making for Shabbat dinner? "Friday nights are pretty standard," she laughs, but admits that half of her dishes will come from Facebook. She'll be eating chicken soup and shwarma-flavoured roast chicken, with potato kugel and chocolate brownies sourced from the group.
Visit the Facebook group here
