Diana Kennedys cookbook is displayed on a kitchen table at her house in San Pablo. She takes afternoon tea in a china cup. Photograph: Toms Bravo/Reuters
Kennedy was captivated by Mexico Citys colourful markets full of exotic ingredients, and started learning to cook dishes from friends and their domestic workers. The couples maid from Guerrero taught her to make her first tamale a pre-Hispanic stuffed steamed doughy dish the recipe for which appears in one of her cookbooks.
Kennedys fascination was fuelled by the diverse flavours and ingredients she encountered while accompanying her husband on assignment and exploring far-flung villages alone on rickety chicken buses. Her first trip to Oaxaca the southern state which later became the subject for one of her books was made with the poet Irene Nicholson in the Times Triumph sports car. These were wonderful adventures, I would visit markets, I tried everything and wrote it all down.
During their eight years in Mexico City, the couples penthouse became a social hub for visiting dignitaries, and Dianas burgeoning knowledge of Mexican cuisine started to gain recognition. It caught the eye of the Times food writer Craig Claiborne, whom Kennedy credits with changing her life.
In 1969 by this time a widow living in New York Kennedy started giving cookery classes at home to make ends meet, teaching unusual dishes like papadzules egg-stuffed enchiladas from the Yucatn and shrimps in a pumpkin seed sauce from Tamaulipas.
A subsequent article by Claiborne landed Kennedy her first book deal with Harpers Row. She spent much of the next two years travelling to remote corners of Mexico talking to humble cooks, documenting old family recipes, and learning traditional preparation and cooking techniques. The Essentials of Mexican Cooking published in 1972 was an instant classic, and introduced the English-speaking world to authentic Mexican cuisine.
Each subsequent book was similarly fastidiously researched by Kennedy, and together they read like a collection of anthropological essays on regional cultures explained through native plants, rituals and recipes.
These are culinary adventures that nobody will ever have. The cooks dont exist any more, the ambience is not there any more I learned my trade travelling the length and breadth of Mexico, sleeping in my Nissan truck. Every book is a different phase of my life and learning, she said.
Forty years ago Kennedy bought land on the edge of the pretty village of San Pancho in Michoacn, nestled at the foothills of the Sierra Madre Occidental mountains and the pine-oak forests where monarch butterflies descend each winter.
An exquisitely tiled open-plan kitchen is the heart of the eco-adobe home she built, where Kennedy still holds boot camps for budding chefs and diehard fans. Prince Charles has dined here; the Rockefellers and Glenn Close have visited. Bottles of homemade banana, pineapple and red wine vinegars are lined up on the windowsill; her eclectic pottery collection would not be out of place in a museum.
Kennedys curiosity has not diminished with age. She is interested in new techniques and trends, but passionately believes that cooking great food is about understanding ingredients and respecting traditions. Tamales must be made with lard; tortillas with native corn; salsa verde with small green tomatoes; and bread raised without sugar. Shes infuriated by celebrity chefs who wear their hair down in the kitchen, as well as by plagiarism of her work, waste, fusion food and sous vide cooking.
I dont criticise for the sake of it, only if something is fundamentally wrong and the frivolous recipe is misleading the public. Its based on my experiences bad work being passed off as good drives me mad.
Kennedys legacy is guaranteed by her writings, but she hopes her organic gardens filled with a rich mix of edible, aromatic, medicinal and decorative plants will also be studied and preserved.
The documentary has given her occasion to reflect upon an extraordinary life, but Kennedy has no plans for slowing down or lowering her standards. She walks 40 minutes each afternoon with small weights strapped to her arms, and still drives her double cabin Nissan truck, something she intends to do for at least a few more years.
I think I can hit 100 thats when my driving licence expires.