A few weeks ago I got a message from Gilvaldo Santos, a bookseller in São Paulo, asking whether I’d heard of a children’s cookbook called Cozinha para brincar (Cooking for Fun).

I hadn’t.

He sent me some images of a perkily designed book, printed in 1970. It looked like the kind of thing a supermarket might give away – and, in fact, the book was produced by Nestlé’s Center for Home Economics. Lots of the recipes call for Nestlé products.

It seemed pretty unremarkable.

But Gilvaldo sent it to me for its short preface.

“I’m like you: I also like to cook little things sometime, That’s why I have a book of recipes for grownups, just as you have one here for the age of important games.

“These are great experiments: including because afterwards you eat the ‘experiments.’ Even the ‘big people’ in your house are going to want to eat them. That’s when you can say to visitors: I made that!

“And the visitors will praise you so so much that they’re going to look like fireworks, like the ones that burst at night in the sky in a shower of a thousand golden stars.”

Beneath it, a signature: CLARICE LISPECTOR.

Those words transformed this unremarkable book into something truly rare. I spent five years writing Why This World, a biography of Clarice Lispector. I then spent nearly two decades translating and publishing her complete works in English. In all those years, I have never heard a reference to this book, and when I started trying to learn more about it, I discovered that it existed nowhere else: no copies in Brazil, no copies anywhere else. As far as I could tell, Gilvaldo’s copy was unique.

I have collected Brazilian books for nearly 30 years. I started as a student, a few years before the internet became widespread. I would prowl the used bookstores in downtown Rio; then, when I began to work on Why This World, I started buying the books I needed for that project. Over the years, I got to know the Brazilian bibliography. And I discovered something unexpected, which was how many rare Brazilian books look nothing at all like “rare books”: not the first editions of some famous old classic, bound in red morocco. Instead, a lot of them looked a lot like Cozinha para brincar: inexpensive, published in living memory – and impossible to find. Some only existed in a single copy.

There were reasons for this. The hot and humid climate, especially of Rio de Janeiro, is tough on paper: I can tell a book is Brazilian from the fungal smell alone. The big cities are crowded; most people live in small apartments, including the people who are the main book buyers anywhere: professors, journalists, writers, and the like. Books get mouldy; they get shuffled around; and the result is that many simply got lost.

This one nearly had too. Cozinha para brincar was odd. Someone had put a lot of work into it. The colourful drawings were by Odiléa Helena Setti Toscano, a graphic designer who created bright murals for the São Paulo Metro. The name was new to me, and I wondered whether she had known Clarice, and whether I could have met her before she died in 2015: in the 20 years since I started interviewing people for my biography, nearly all of Clarice’s contemporaries have departed. Even the younger people who had known her, people a generation younger, were dying. The only friend left was the artist Maria Bonomi, who just turned 90. Half a century after her death in 1977, the only people left with memories of Clarice had known her as children or very young adults.

Odiléa illustrated the book with care, but other things in the book were odd. The book was divided into seven chapters, and all seven had the exact same introduction: “Here are some important recipes for whoever wants to be a real master chef. They’re the base for your main courses. Choose among them the pie crust that never misses, the mayonnaise that doesn’t break, and the filling-icing that you can use on every cake.”

The repetition of this text might offer a clue to the book’s rarity. Perhaps the error meant the book was never distributed. Another clue was the absence of an International Standard Book Number. These are usually assigned by the legal depository library in every country, the institution that, by law, collects every book published in that country: in the US, this is the Library of Congress. It is unusual, though not impossible, that a Brazilian book would not be found in the Biblioteca Nacional in Rio de Janeiro.

The rarity of this book, the lack of any references to it, make it impossible to know what role Clarice might have had in making it. It would be hilarious to know, for example, if the great Clarice herself really wrote a recipe for “the cocktail that calms down Daddy.” Clarice, like many Brazilians of her class, had domestic help, and was not much of a cook: her son didn’t recall her ever making “so much as a coffee.”

Nonetheless, she did write four children’s books, and the tone of the preface is recognisably hers. She had written lots of journalism for what was then called the “women’s pages.” She had also done the kind of hackwork that is found here: she was once paid by Pond’s face cream to promote their products in her newspaper columns. After she separated from her diplomat husband and returned to Brazil in 1959, she was constantly in need of money.

Yet though this unknown and apparently unique book might add little to what we already know about Clarice’s life and work, it is nevertheless thrilling to find it. The lives of every great writer are filled with such commonplace assignments, and they are humanising reminders of the times in which this great writer lived: of a time when even the immense Clarice might be asked to weigh in with her views on chocolate mousse (using Nestlé’s Semi-Bitter Superior Chocolate, of course.) This book lets us imagine Clarice, so long since transformed into a mythical titan of Brazilian literature, as a middle-aged, middle-class woman: in the kitchen, taking on some extra work, trying to make ends meet.

So many of her female protagonists spend their days in exactly this way, and until she wrote about those middle-class housewives, their days and their lives had hardly been considered the subjects of high literature. An afternoon in the kitchen with the kids: the perfect setup for one of her shattering stories or novels. More than its rarity, then, that is why this book is so touching to me: because the lives of the women and children who might have used this book are the raw ingredients that this greatest of modern writers transformed into her abiding art.