'I live in a country that's sort of fat-phobic and it just doesn't make sense to me; fat doesn't make us fat," Michael Ruhlman tells me as we start our conversation about his book, The Book of Schmaltz: Love Song to a Forgotten Fat.

The country he is talking about is America, but it's a statement that rings true for the UK as well, in fact for most Western countries nowadays. It was this "love of fat" that led Ruhlman, author and trained chef, to discover the joys of the most traditionally Jewish of fats - schmaltz.

Schmaltz is rendered fat – usually chicken - that originated in Central Europe and is historically identified with Ashkenazi Jewish cuisine.

"I've always known what schmaltz is and I've always been curious about working with it," says Ruhlman. But his Damascene moment came at a party five years ago, chatting to a neighbour, Lois Baron, who had to make a quick getaway.

"She said: 'I have to leave, I have to go make my schmaltz because the high holidays are nearing,' and I was like 'wow, somebody's making schmaltz, I've found my teacher!' And I asked her to show me the ways about schmaltz."

Ruhlman has written 13 other books on cooking and says he uses his books to educate himself on foods and techniques that are new to him. "I write books to search and look into a subject and that's what I was doing with schmaltz."

In fact, it was this need to know a subject intimately, that led him to write about food in the first place. Ruhlman trained as a journalist, working at the New York Times in his 20s, before leaving to pursue a career as a novelist - "I did write novels but they didn't get published" - and landing a non-fiction book contract. In 1996 he visited the Culinary Institute of America, the world's top culinary school, to research his second book, The Making of a Chef: Mastering Heat at the Culinary Institute of America.

"I was writing a book about what you needed to do to become a chef; while I was there I realised I couldn't just write about it, so I became a professional chef in order to write that book."

Before writing The Book of Schmaltz he taught himself to make it, but he insists it's easy to make and he perfected it in one try. "I said, 'Lois, how do you make schmaltz?' She told me. That's how easy it is."

The ease of making schmaltz - along with the affordability of ingredients and its varied uses - was one of the reasons for its historical prevalence in Jewish cooking. Michael Wex, author of the recently published Rhapsody in Schmaltz: Yiddish Food and Why We Can't Stop Eating It - another book extolling the virtues of this distinctive fat - says that he has noticed that schmaltz as a modern foodstuff is "paralleling certain trends in wider society". He points to the recent popularity of deli-style restaurants, such as Delancey and Co (in Goodge Street) and Stoke Newington's The Good Egg. "To a degree the immigrant associations of this type of food have gone from being something you were ashamed of to a point of pride; plus it's no longer the food of poverty."

Wex grew up in a strictly Orthodox family, hearing stories of his father eating "radishes dipped in schmaltz for breakfast in Poland". He says that schmaltz has to be at the centre of any movement in popularity of traditionally "Jewish" foods "because it was schmaltz that pretty much distinguished Jews and non-Jews in Eastern Europe".

He says that anything cooked with schmaltz has such a "schmaltzy zest" - something Ruhlman describes as "an umami quality" - that, beyond the obvious differences resulting from kashrut (beef or pork for instance) was the main point of distinction between a Jewish and non-Jewish version of the same dish.

He says: "We'll know schmaltz has really 'arrived' when it gets picked up by cooks who aren't trying to cook 'Jewish' - and are using it simply for its flavour."

Ruhlman is a perfect example, as he is not actually Jewish.

"I've always been interested in Jewish culture," Ruhlman says. "The extraordinary and bizarre persecution throughout Jews' history astonishes me. Combine that with my interest in food and culture - how does this culture affect that cuisine - it all came together in this extraordinary fat."

He points to the "great cholent" recipe from his book, and says that chopped liver made with schmaltz "is like no other chopped liver - it's fabulous." He's also included some surprising recipes, such as those for cookies and brioche. Sweet items aren't what we think of when we think of schmaltz but Ruhlman insists that "it's amazing, very elegant".

Most of the recipes are kosher-friendly, with the exception of a couple of the less traditional, such as the brioche. But he says that the response - from Jews and non-Jews alike - has been positive. His family and friends are "sort of amazed and surprised by it". His neighbour, Lois, "loved" it and Jewish friends and chefs feel the same: "Jewish cooks love seeing their cuisine given respect."

So could this be the start of a "schmaltz revolution"? Try it for yourself and find out…

The Book of Schmaltz: Love Song to a Forgotten Fat by Michael Ruhlman is published by Little, Brown and Company; (ruhlman.com).

Rhapsody in Schmaltz: Yiddish Food and Why We Can't Stop Eating It, Michael Wex, St Martin's Press (michaelwex.com)