To make sense of it all, I ask a local friend to take us on a tour. Jason Thomas Fritz is a Mexican gastronome who has taken it upon himself to be the authority on street food in Mexico City. He roams the streets learning about the regional and esoteric traders that come into the city every day and is obsessed with finding the best of what the city has to offer; from carnitas to suadero, chorizo to pastor, cecina to trompa and everything in between. In a city where more than 10 million people eat on the street daily, Jason is the guy who knows what’s what and where to go, and a tour with him is a gateway into the soul of Mexico City’s rich culinary landscape.

We meet Jason at Zocalo Square – where Mexicans have been gathering since Aztec times – on a sun-drenched morning. After the usual dignitaries, we embark on a brisk walk into the eye of a whirlwind taco tour of the city. Our first stop is a man who specialises in tacos de canasta (basket tacos). These half-moon-shaped pockets of corn are a hallmark of Mexico City and made by folding hot tortillas on themselves after being filled with ingredients such as mole verde (green mole), chicharron presando (pressed pig skin) and frijoles (beans). They’re then tessellated upon each other in a basket (canasta), covered with towels and blue plastic sheets and left to steam and soften to an almost gummy texture, until a hungry customer comes to order. You’ll often hear a cyclist shout out ‘tacos de canasta, tacos de canasta!’ whilst wandering the streets. I highly recommend you stop him and order a couple – they’re rich, soft, chewy, tender and incredibly moreish, especially with a dollop of acidic and sharp salsa especiale served atop for good measure.

Our next stop is 100 metres down the road – a shop that specialises in tacos de suadero (thinly cut braised brisket) and tripa (tripe) tacos. This is all it sells and all it has ever sold since 1957. Upon ordering, the taquero dips a stack of tortillas in the bubbling cauldron of fat that the brisket has been confiting in. Like a hand of cards, the burly taco croupier shuffles the tortillas onto a convex cast-iron comal and warms them. As the hot, fatty tortillas sizzle and puff up from the intense heat of the steel beneath, a heap of wobbly tripe appears on the block, which is deftly hacked into a million little pieces through the use of a monstrous cleaver. This mixture is then added to the steaming hot tortilla and flipped over, so as to amalgamate the tripe and tortilla.

A couple of minutes of frying later, the question ‘con todo?’ is fired at you, meaning ‘with everything?’, and of course, our answer like it always ought to be when asked that question, is yes. He adds a spoonful of confit brisket to the tripe-tortilla mix, turning this ensemble into what’s known as a campechano (mixed meat) taco. A splotch of fiery habanero salsa, minced coriander and raw white onion are the final flourishes of his performance. A plate lined with a plastic bag – a common theme in Mexico which saves on washing up but is detrimental to the environment – is passed to us with a grunt of ‘provecho’ (enjoy) before he moves on to the next order.

It might have been the process of seeing this masterpiece being assembled, the absolute joy of being in Mexico City or just raw reverence, but I don’t think I’ve ever tasted anything quite so heart-rendingly delicious. It’s the closest thing to a perfect taco I’ve eaten – the crispy tripe is so clean and gelatinous; the hot, fatty tortillas have the perfect amount of gummy, corny give; the suadero is rich and beefy but not too fatty and the salsa is fiery, acidic and complements the floral papalo (an acidic, medicinal Mexican herb) that I’ve personally added from the huge bouquet left on the counter for customers to garnish. It’s simply breathtaking. And costs 30p.

We’re virtually dragged away, mid-swoon, to our next taqueria, Los Cucoyos. It’s famous for its late-night vibe and for serving some of the best offal tacos in Mexico City. Los Cucoyos never really closes as it doesn’t have a shutter and its taquero, Alberto, is an affable man who’s stood in the same spot years, taking genuine pleasure in seeing customers eat his food. My first order is manciza (cow’s head) – rich, delectable and irony. I devour two without a thought and move straight onto a trompa (pig’s snout) taco which is made by braising pig snouts in a cauldron of pork fat. It’s delicious, unique and everything I love about Mexican food: accessible, cheap, waste-less and somehow fresh, spicy, salty, rich and satiating all at once. At this point we’re six tacos in – I spot a job advert for a taquero and start to seriously consider it.

We continue the tour by wandering the streets of Centro Historico, the grand, aged buildings of colonial Spanish rule overshadowing us. The conversation is only about Mexican food – who does what and where; the complexities; the idiosyncrasies; the layers; the salsas; what makes this city so special; the history of the cuisine; the importance of access to cheap food… This is a common theme in Mexico. People don’t eat to live; there’s a passion for food here that is so deeply ingrained into society that they just talk, think and procrastinate about it all of the time. As a chef who’s made it his life’s work to understand this country’s pre-hispanic cuisine, I’ve never felt more at home.

We wander into a hole-in-the-wall quesadilla and tortilleria that specialises in huitlacoche, or corn smut as it’s known in America. Traditionally discarded in the USA, huitlacoche is a perfect example of the Mexican approach to food – it is revered and seen as a true delicacy rather than a waste product with no use. Quite often compared to truffle, huitlacoche is a fungus that takes over the corn cob and infects the kernels. The result is a creamy, not too sweet, earthy flavour that when ensconced within a hot, freshly pressed corn blanket with melted, creamy Oaxaca cheese and a heavy-handed helping of the zingy green and smoky red salsas is celestial. As a Mexican chef friend of mine would say, ‘Lord have mercy’ – the flavours tick all of the Mexican boxes: sweet, spicy, salty, herbaceous and earthy. We order another for the road.

We ramble on, the smell of pork fat, corn and stewing meats (guisados) wafting through our noses as we pass the interminable, multicoloured shacks and street food stalls that grace the pavements. The sheer scale of food vendors in this city continues to perplex. They’re everywhere!

Jason stops at a dusty street corner where three ladies are huddled over a comal. He explains to us that the same family has sold tlacoyos (fat torpedo-shaped corn tortillas filled with beans and meat) here for three generations. They grow their own corn 100 miles away and travel into the city everyday with twenty kilos of masa, cheese and beans strapped to their backs. Their story is one of struggle and hard graft, but the pride they show in what they do beats that of any chef I’ve met. It’s a perfect example of the Mexican approach to life – these are a humble people who do the best they can with what they have, with immodesty, contentment and most importantly, pride. The tlacoyos are gut-wrenchingly filling and hugely enjoyable. Emotions towards this city, its people and food are at an all-time high.

Our penultimate stop is at the hole-in-the-wall taqueria El Huequito, for arguably the best al pastor in Mexico City. This classification will ruffle a few feathers, of course. Who makes the best tacos al pastor – originally brought over by Lebanese textile merchants in the 1950s as lamb shawarmas and repurposed into pork tacos by Mexicans – is a subject of great dispute in Mexico City. Think of it in the same way as how fish and chips are disputed in the UK, pizza in Naples or ramen in Tokyo.

You could spend a month in Mexico City just eating al pastor and still not cover the limitless styles and small variances each trader has developed. A common blueprint, however, sees thin slices of pork neck and belly marinated in guajillo chilli, ancho, achiote for colour, cider vinegar and spices, before being placed on top of each other to form a V-shaped trompo or doner kebab-style spit. The column of meat is then crowned with a peeled pineapple and cooked over a blazing heat. As an order comes in, the taquero deftly carves super-thin vertical slices of pork onto a fresh tortilla and theatrically snips a sweet sliver of that pineapple onto the taco. If you’re lucky – which you probably will be – the taquero will be something of a performer and you’ll see all kinds of pineapple trickery involving flying pineapple slices – it’s a sight to behold. The point of difference at El Huequito is that the tortilla is rolled up into a cigar-shaped taco with the pork loin filling enveloped within, alongside a slew of caramelised onions. The result is a mouthful of sweet, porky, oniony goodness. One is never enough. Neither is two.

By this point we’re so many tacos deep and have walked so far things begin to get hazy. We make a final bee-line for a carnitas joint. Johnathan Gold once wrote, ‘Well-made carnitas may be at the centre of the genius of the Mexican kitchen, a process evolved to draw the maximum fragrance out of something already inherently fragrant, pork seasoned with itself, and salt, and time’. This is exactly what this final taco delivers – magical, porky, fragrant goodness and the prescription for a long afternoon siesta to recover before we hit the streets in search of taco nirvana once again.

In the following days we gorge on breakfast tamales, frijoles negro con huevos, chilaquiles camotes, elote, chiles en nogada and so much more. We go to El Vilsito, a taqueria that’s a car garage by day and an incredible pastor joint by night, before visiting Contramar, a seafood restaurant famous for serving some of the best fish dishes known to man. We also have a meal at Pujol, a restaurant that is ranked thirteenth in the world for some of the most refined Mexican food around, and enjoy a counter-based tasting menu echoing the Kaiseki restaurants of Japan at Emilia. Such is the diversity of this incredible place.

I doubt anybody could ever capture the dynamism of Mexico City and its people, its food or its culture in a short article like this. It’s a mysteriously captivating place which demands many returns. I’ve been coming back here for fifteen years and it’s never been the same. And long may that continue.