It's 9am on a Saturday morning in Port Louis, the capital of Mauritius. Beside me an old dude gazes at a rail that's crammed with an array of jazzy polyester boxers. He selects his favourite pair, pays up, and then joins me in a queue that wiggles through the maze of market stalls.

We wait together patiently, watching as a lady rolls up the sleeves of her turquoise polka-dot dress and starts kneading dough with the expertise of someone who's done this a million times before. She wipes her hands on her flowery apron, then ladles lima beans and rougaille, a tomato, onion and garlic sauce, into my roti. She then hands it to me on a sheet of paper, its oily weight lolling off the sides. Old dude urges me to take a nibble. And I do.

No, this is not an Indian Ocean honeymoon gone wrong – although you'd be forgiven for thinking so. I have not been jilted, and I'm not here with my fiancé, my paunchy husband of 40 years, or a faultless new beau. I'm happily alone. Forget scampering along the beach to secure a sun lounger at 6am, stuffing myself silly at the buffet breakfast or anything else that typically comes with a trip to this beach-packed island – I'm here on a different mission: to learn about Mauritius via its food. This – I think, taking a giant bite – may just be the world's greatest history lesson.

My spicy roti is just the beginning, or rather the middle. "Mauritius is a volcanic island so there's no natural population," my guide, Yianna, from independent tour company MyMoris explains. "The Arabs were the first to come in 975AD – they put the island on the map. The Portuguese arrived on the island in the early 16th century; they found jungle and left. The Dutch followed in 1598, a time when the island was known as 'Rat Island', as the boats were filled with rats. They ate all our dodo eggs. Then in 1715 the French conquered the island and imported slaves, but the British took over in the early 19th century and abolished slavery, instead hiring half a million workers from India who came to work in the sugarcane fields. That," she says, pointing to a smear of something on my face, "is why you're eating roti here today."

The roti is just one part of the island's culinary history, where Indian, Chinese, European and African influences mingle together in the tourist-free backstreets of the capital. We continue wandering through Trou Fanfaron market, the stalls at the side overlooking a swarm of brightly painted buses that are waiting to scoop up the last few punters keen to take the trundling journey along the coast.

Inside, shoulder-to-shoulder stands threaten to fold beneath the weight of undies, nighties and tat, while other tables buckle under giant mounds of brède – the ubiquitous term used to describe any leafy greens that are thrown into soups, stews and curries. At one stall a cluster of 80-somethings and eight-year-olds jostle for a portion of small, hot-pink beads. "Nuts," Yianna explains, "we dye them. Mauritians love to eat pink food."

That may be true, but today colours seems irrelevant. Pink, brown, white – double-figure queues group together at virtually every stall and shop in a city. Custard-coloured buildings are on the cusp of collapse – in that crumbly way that's charming in any country other than your own – and the hot, still air is filled with the scent of spices, exhaust fumes and salt. This is a port city, after all.

We wander on, soon stopping at the battered two-storey high wooden doors of what looks like the most popular breakfast spot in town. A teenager leans on the door's peeling tomato-red and Chelsea-blue paint – he's part of the family that's been dishing out gato pima to loyal customers for decades. The dark brown, deep-fried balls of split peas, chilli, coriander and spring onions are tossed into a paper bag before they're devoured by passers by, their mouths hanging open in that familiar way that comes when you greedily put any roasting-hot food into your mouth. I do the same, knocked back by the holy trinity of heat, spice and teeth-threatening crunch.

The roti is just one part of the island's culinary history

Nearby, in a shady, metre-wide covered alleyway, things are much less frantic. I take a seat at one of three red plastic tables before a portion of plump chicken dumplings are plopped into a flowery bowl and placed in front of me. "The first wave of Chinese migration was in the 1780s. The artisans worked for French families in the capital, and set up shops and restaurants like this one," Yianna tells me. I spoon some chilli onto the dumplings and finish them in minutes, my thoughts instantly diverting to dessert.

Nearby I hover in the dark and battered shop doorway of a shop called Lilinne's. I'm handed a paper plate of unidentifiable dishes, including gato zinzli – squidgy, sweet parcels coated in sesame seeds and filled with black lentils, an adaptation of the traditional red beans that Lilinne's grandpa couldn't source when he opened here in the 1950s. The shop may be largely unchanged, but today, the capital's China Town (a term given to the area in the 1980s when labelling Chinese-inhabited areas was all the rage) is home to new additions, from the colourful street art that tarts up the neighbourhood's blackened walls, to rooftop pagodas that act as peaceful sanctuaries in a city that's joyfully hectic with horns and hustlers.

Forget the swaying palms and powdery sand: it's this chaotic jumble of cultures that makes Mauritius hypnotic. We walk on, sidestepping giant sacks of spices, lentils and beans that spill out of shop fronts on the pavements. Old wooden shelves droop beneath the weight of ludicrously stinky dried fish, their tails wedged into any available crevice in a Jenga-style structure. A lady bags some up to buy, then eyes up the other end of the shelf, where fruity shower gels promise to wash away the whiff. Convenience stores don't get better than this.

But a trip to the capital doesn't just have to be a case of meal hopping. Visually it's fascinating – from the fancy iron gates of Central Market that are dedicated to Queen Victoria, to the turquoise and white volcanic stone of the Jummah mosque, which stands serenely on a traffic-clogged street, the tree branches in its garden laden with the fruit of mangoes and almonds. Fruit trees? In a capital? "The French made a law that every house must have a fruit tree in the garden," Yianna explains. "It's likely that a house was on this site during the French period, and they decided to build the mosque around the trees instead of cutting them down." Today, breadfruit, tamarind and lychee still dot the city's gardens.

We cut through the vast Central Market in search of our last meal. Beneath its lofty ceilings stall owners shout out trying to sell me fruit, vegetables and herbal aphrodisiacs. Tempting, but not today.

Instead we arrive at a stall. What its owner Ameen lacks in customer service he makes up for with PR know-how. A sign displayed on his tiny stand's glass cabinet boldly claims that he's the number one gato patate maker in Mauritius – a Hindu sweet potato speciality he's been serving up to customers for 40 years.

He hands me one. The treacle-coloured parcel is cold and, er, flaccid in my hand. It looks unpleasant. It feels unpleasant. I take a reluctant bite and Ameen's face finally crinkles into a happy grin. He knows. Forget the rum I've guzzled, the empty beaches or the mountains I've climbed – it's this coconutty sweet potato cake that I think back to from my trip to Mauritius. If only all history lessons could be so good.

MyMoris offers a range of food and cultural tours on the island, mymoris.mu; Beachcomber Dinarobin offers nightly rates from £250 per room per night, beachcomber-hotels.com; For more information see tourism-mauritius.mu