One of Doña Herlinda Olivas’ earliest memories is stealing raisins from her grandmother.

“I was 4 or 5 years old and I would whine ‘Abuelita, give me a few.’ ‘No, no, no, go outside and play,’ she would say, and the ladies would say ‘Oh, Rafaelita, give her some raisins, she loves them’ but my grandmother would refuse. Then, the lady of the house would always sneak me a couple to eat. ”

In San Pedro de Atocpan, their tiny hometown, Doña Olivas’ grandmother was an important person. She was one of only three local molenderas (mole makers) and her neighbors often hired her to help them prepare massive quantities of mole for special occasions. Doña Olivas’ co-conspirators were women from local families that would gather together on straw mats, each with a metate in front of them, grinding the chiles, seeds and nuts that went into her grandmother’s famous mole recipe.

“Maybe the reason that I like making mole today,” muses Doña Olivas, “is from watching my grandmother order everyone around.”

Now a grandmother herself, Doña Olivas’ eyes twinkle in the middle of her weather-worn face. Braided into her jet black hair are electric-green pieces of woven fabric that that same grandmother hand stitched over 60 years ago.

That fabric, the familiar scrape of the volcanic rock metate, and the perfume of chiles in the air is the heritage that was passed down to Doña Olivas from her grandparents. She has now been making mole for more than 30 years and was one of the original organizers of the first San Pedro Atocpan Mole Festival in 1977. Designed to showcase all the incredible mole coming out of San Pedro, the festival began with only eight families and now includes over 39 restaurants according to Doña Olivas, in addition to dozens of stands where you can purchase mole in paste or powder by the kilogram.

San Pedro Atocpan is located in Milpa Alta, by far the most rural of Mexico City’s 16 boroughs. Surrounding the town are miles of corn, amaranth and nopal cactus fields and within its boundaries are hundreds of families making mole. The town produces approximately 60% of all the mole in country and 90% of what’s on the shelves and in the markets of Mexico City. Long a forgotten backwater, in the 1940s and 50s, the town of San Pedro was put on the map when a handful of families ventured into the city to sell mole at markets and shops. Those first commercial pioneers were so successful that most of the town followed suit – now a whopping 90% of the town’s residents are involved in mole production.

While the word brings to mind a common image in most people’s minds – a deep brown sauce draped over a piece of chicken sprinkled with a few sesame seeds – mole is perhaps one of the most misunderstood Mexican staples outside of the country. It’s been called chocolate sauce, “Mexican curry,” or even gravy, but as with most delicious concoctions, the essence of mole is not so easily defined.

According to Roberto Muñoz’s Mexican gastronomy encyclopedia, there are 71 types of mole in Mexico (and a few individual variations within those types). With only a handful of exceptions all moles start with chiles, but they can be dried or fresh, red or green, spicy or mild.

Mole paste is made by grinding those chiles – historically on a metate, nowadays in an industrial grinder or even a food processor – in combination with any of the following: almonds, pistachios, peanuts, clove, cinnamon, chocolate, sesame seeds, pumpkin seeds, fresh herbs, avocado leaves, oregano, corn, cumin, peppercorns, oats, tomatoes, achiote, black beans, burnt tortillas, day-old bread, bananas, figs, raisins, dates, berries, garlic, thyme, epazote, or animal crackers.

The endless world of combinations of the above ingredients ensure that each mole comes out as its own unique specimen and that everyone has a secret recipe. Moles vary by region, with the center of the country home to the deep chocolate-colored moles of Puebla and Queretaro, Oaxaca serving its signature 7 moles: chichilo, manchamanteles (translation: “the tablecloth stainer”), yellow mole, green mole, black mole, colorado and coloradito, and San Luis Potosi and Zacatecas specializing in a mole rojo (red mole) that is known for its sweetness. Not all moles include chocolate, some are soupy in consistency, and at least half a dozen don’t include chiles.

The moles from San Pedro de Atocpan traditionally include fruit – berries, figs, dates, raisins, prickly pear – and the town is particularly famous for their mole almendrado (almond mole) that has a deep nutty flavor and the consistency of a grainy bechamel.

The word mole comes from the nahuatl word “mulli” which simply means mix or concoction. From the study of pre-Hispanic cuisine, it’s known that many dishes served by the ancient indigenous people of Mexico called for the same ground seeds, corn dough and many other herbs and spices that you’ll find in modern-day mole. Legends recount mole’s accidental “discovery” by the monks and nuns of the State of Puebla, but the dish we eat today is most likely a combination of pre-Hispanic and colonial cooking, a blend of species, chiles and proteins both native to the Americans and brought across the ocean by the Europeans – a story not unlike that of the majority of Mexico’s most iconic dishes.

While these days you can get mole any day of the week in a decent-sized Mexican city, the dish remains one that is traditional for special occasions – weddings, baptisms, quinceañeras – especially when its hand-ground and homemade.

Making this dish takes time and recipes are often passed down from generation to generation. At one time groups of women, like those led by Doña Olivas’ grandmother, came together to grind out the kilos of mole paste needed for large events, and although many towns now have mills where you can take your ingredients to have them ground, mole-making at home is still a culinary ritual, and not just in the rural outskirts of the country.

The National Mole Festival in San Pedro, held every year for three weeks in October, is a chance for locals to show off their talents and ply customers with spoonful upon spoonful of mole samples. Piles of powder are elaborately decorated with images befitting the queen of Mexican sauces with the Virgin of Guadalupe, wild turkeys and fields of wild flowers all making appearances. Tucked among all that mole are candied pecan vendors, hawkers of broad clay mole pots, stacks of amaranth bars for sale and even pony rides for the kiddos. A haze of toasting tortillas will follow you across the campgrounds.

The children and grandchildren of those first mole makers are now running the festival’s stands and restaurants. Among them are Doña Olivas’ seven children and her fifteen or so grandchildren. They’ve each stepped into the shoes of an earlier generation to carry on the mole making tradition.

“One of my kids said recently in a town meeting, ‘I’m first a molero, then a doctor. I make mole. I was born from mole.’” Doña Olivas chuckles, “What do you think of that? We are all mole makers.”