All over Mexico City, women squat outside around a comal (low griddle) and press out thin ovals of corn dough to make tortillas. They’ll fill them to order with your choice of shredded and marinated chicken tinga, squash blossom, a corn fungus called huitlacoche or many other options.

These women are the first people I look for when I land in Mexico City, and they aren’t hard to find. I stand under colourful umbrellas, watching as a street vendor scoops out blue or yellow corn dough, shaping it wide and oblong. As she slaps the tortilla on the comal to cook, I ask her to fill mine with huitlacoche, and she places the so-called ‘Mexican truffles’ parallel to the tortilla to warm as it cooks. When the tortilla begins to brown, she’ll slip the huitlacoche onto one side and fold the tortilla around it forming a semi-circle, and then motions towards the wealth of toppings.

It’s really confusing to people who think they know something about Mexican food

“Rojo o verde?” she said, asking my salsa preference (‘red or green’?). I always choose both – the heat of the toppings and the comal combine to create the quintessential flavour of Mexico City’s streets, the one I miss most when I’m away. This quesadilla is what I recommend to friends when they first come to Mexico City, but, I always warn them: if you’re expecting your quesadilla to have cheese, you may be sorely disappointed. Quesadillas in Mexico City don’t automatically come with cheese. You’ll have to specially request them ‘con queso’.

Lots of visitors ask, “But doesn’t the word ‘queso’ mean ‘cheese’?” said Lydia Carey, tour guide and author of Mexico City Streets: La Roma. “It’s really confusing to people who think they know something about Mexican food,” she laughed. Yes, the word ‘quesadilla’ comes from a combination of ‘queso’ and ‘tortilla’, but in the country’s capital, the dish doesn’t always add up to the sum of its parts.

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The lack of cheese in Mexico City’s quesadillas is a point of contention between Chilangos (the city’s residents) and the rest of the country, and a point of confusion for travellers who assume that their quesadilla will come with queso, as it does in the rest of Mexico. In recent years, the issue has become a popular topic for cross-country quarrels and fodder for memes.

While it might be a matter of friendly competitiveness among Mexicans, for travellers navigating Mexico City’s world-renowned street food scene – with its mystifying maze of unsigned stalls, subtle differences between the various forms of corn flour stuffed with meat and vegetables, and multiple types of taco stands – understanding the nuances of the local quesadilla helps them order exactly the delicacy they’d like to eat – with or without cheese.

When people ask Carey what the difference is between a quesadilla without cheese and a taco, she says “my brain explodes”. As she explains it, they’re distinguished by a series of subtle nuances, including both the tortilla (shape and size) and what’s in it (usually corn fungus, mushrooms, chicken tinga, squash blossoms and occasionally peppers or potatoes with sausage). There’s also a lot of crossover of typical fillings with one of Mexico City’s other classic foods, tacos de guisados (tacos filled with hearty, homestyle stews), but the shape is slightly different.

Journalist and editor Laura Martínez, founder of the website Mi blog es tu blog, says that to her, the differences between quesadillas and tacos are like the differences between pasta shapes. And if people can understand that there’s a difference between fettuccine and spaghetti, surely they can master tacos and quesadillas, regardless of whether there’s cheese inside. “I describe it to people as a novelty,” said Carey, of the cheese-less, local quirk.

On Amazon, you can purchase T-shirts that say ‘Las Quesadillas Llevan Queso!!’ (‘Quesadillas have cheese!!’), and the internet is full of memes about how the rest of Mexico thinks of quesadillas without cheese: like lemonade without lemons or hot chocolate with no chocolate.

But the idea that the ubiquitous street food even should have cheese isn’t something that even occurs to Chilangos unless it’s brought up. “It’s not a thing we talked about as kids,” Martínez said. But for people like Carey and Anais Martinez (no relation to Laura), owner of Mexico City food tour company The Curious Mexican, it comes up all the time. “For me, it’s normal,” said Anais – a born-and-bred Chilanga. “But for the rest of the country, it’s cheese inside.”

Interestingly, Anais points out that a quesadilla without cheese in Oaxaca is called an ‘empanada’, which could be a surprise for people used to baked or fried hand pies with filling. Meanwhile, what Americans might call a ‘quesadilla’ – two tortillas with cheese and maybe ham inside, would be called a ‘sincronizada’ throughout Mexico. Or, if the tortillas are made with wheat flour rather than corn, a ‘gringa’. What most Mexicans outside of the capital call a ‘quesadilla’ is a single tortilla folded around cheese and other fillings.

“A quesadilla is a tortilla folded in half,” in Mexico City, Anais explained, but a more elongated, oval-shaped tortilla than in a taco, “so you can have more filling in each bite”. That’s just the city’s ‘thing’, she shrugged, referring to Mexico City quesadillas’ lack of cheese. But she also admits that Chilangos like herself get a sense of pride from doing something their own way.

For Carey, an American who has lived in Mexico City for more than a decade, that pride in something so quotidian is a characteristic that’s quintessentially Chilango. “There’s something about the stereotype, an obstinance about being from here,” she said. “Deep down, they know it’s the heart of the country, the economic centre. It’s like they’re saying, ‘We’re from Mexico City, we do things differently here’.”

It’s like they’re saying, ‘We’re from Mexico City, we do things differently here’

And, apparently, they’ve done things differently there for a long time. After eight years of looking for answers, writer, editor and translator Sergio Zepeda de Alba recently dug into the origins of Mexico City's quesadillas for the online magazine Revista Replicante to examine just how far back this cheese-or-no-cheese division goes. According to Zepeda de Alba, The Dictionary of Spanish in Mexico – a compendium of local vocabulary used in Mexico since 1921 – defines the quesadilla simply as a corn or flour tortilla, folded in half and filled with various foods (which may or may not include cheese) that’s fried or cooked on a comal. In other words: the Mexico City definition. Spain’s version of the Oxford English Dictionary, the Royal Spanish Academy, agrees, defining a quesadilla as a corn tortilla stuffed with cheese ‘or other ingredients’, eaten hot.

This definition, which goes against what most of Mexico considers a true quesadilla, lead to a petition two years ago, asking the Royal Spanish Academy to modify the definition to specify that tortillas should include cheese.

After uncovering a reference in Spain to quesadillas from 1490 as a ‘little empanada’ with meat or cheese, Zepeda de Alba believes that quesadillas originate from the word ‘cheese’, but that doesn’t mean it’s the only correct filling. In fact, a variety of 19th-Century quesadilla recipes published in the 900-page tome Cocinero Mexicano (The Mexican Cook), call for “aged or fresh cheese, or goat cheese”, while others call for chicharrones (pork rinds) or brains, but no cheese – suggesting that the two schools of quesadilla thought have run parallel in Mexico for centuries.

In the end, Zepeda de Alba’s article concludes that the evolution of the quesadilla in Mexico City isn’t something that can be traced to single origin, and that the shape and fold of the corn tortilla is what defines it as a quesadilla.

“It’s more than food, it’s a culture thing that glues people together and keeps them talking

For Martínez, the debate over what belongs in a quesadilla is more about communication, and perhaps even social media, than what’s on the plate. “It’s more than food, it’s a culture thing that glues people together and keeps them talking,” she said, comparing it to the battle over whether pineapple should go on pizza. “It becomes a way of people connecting with each other,” she said, more than the actual argument about what we eat.

But to Carey, the divide between quesadillas with and without queso is an intriguing complexity for visitors navigating the world of Mexico City’s street food. “It’s easier for people who come in with a blank slate,” she said. Carey admits she had her own misconceptions when she moved to Mexico – namely thinking that the food would be the same all over the country. “Coming to Mexico City and eating on the street here taught me that everywhere is different.”

Still today, Carey says that walking up to a street food stand and knowing right away how and what to order is both one of the most difficult parts of living in Mexico and the most satisfying. But for quesadillas, it’s not so hard: you just need to remember, if you’re in Mexico City and want cheese on it, ask for your quesadilla ‘con queso’.

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