In a few decades Mumbai will be the biggest city in the world. Already a sprawling megalopolis that stretches out like a giant crab’s claw, you can travel from the tip to the north for two hours by train or car without breaching its borders. Its growth – fuelled by trading cottons, silks and tobacco overseas for the past 500 years – has beckoned workers from all over India, transforming it into a glorious mix of cultures, people and food. It has made it what it is today: the best place in the world to get a snapshot of Indian food from all around the country.

Among these offerings, the vegetarian food is unrivalled. India is home to half a billion vegetarians, which is more than the rest of the world’s vegetarians put together; naturally, many of India’s greatest hits are served here. It is a vegetarian’s paradise.

On my last trip to Mumbai I arrived on a 6am flight, intentionally, so that I could squeeze in as many meals as possible during the next 24 hours. I was picked up, as always, in an old Padmini taxi by my uncle, Mahesh and friend, Sam. In all the years I’ve been travelling to the city, our plan has always been the same: to eat the best food in the city, as much as possible, with no rules (except the obvious abstention of meat).

As we moved across town, past the rickshaws and motorbikes carrying families of five, we smelled on the roadside what the city was eating for breakfast: fresh aloo parathas, big vats of steaming poha: flattened rice with caramelised onions, potatoes and lemon. Sandwiched between them, the chai-wallahs, with their muzzein-like calls “chai, chai, chai”, were pouring tea from great heights in an act of showmanship.

Around every corner, another smell, another stall. Amid the smoke and steam of the city, you can eat everything here from lace-edged dosas from the south to creamy chole (chickpeas) with flying-saucer bread baturas from the heart of Punjab, at all times of the day. The best places tend to have one thing in common: they do one thing very well. The egg bhurji man I met near Churchgate station had been cooking that same recipe for 35 years, while Sanjay Singh, a sandwich-wallah in Kala Ghoda had been making his sandwiches for 22 years. Both are masters of their craft.

This street-level excellence means that everyone agrees that expensive doesn’t equal the best, not here in Mumbai. Few follow food critics, most prefer to follow their nose, or the words of their friends. It works. Lawyers, students and manual workers all queue together at the best places in a rare show of egalitarianism in a city otherwise split by race, caste and money.

We stopped at Kyani and Co (JSS Road, opposite Metro Cinema, Jer Mahal Estate, Marine Lines, +91 22 3015 0864; breakfast for two £3.50). This is a Parsi cafe, where we ordered akuri: super-creamy scrambled eggs mixed with green chillies, tomatoes and onions and served on toast. Pow! What a start to the day. For a small community, the Parsis have had an enormous impact on Mumbai food culture with slow-paced, airy cafes and an obsession with eedu per (eggs on everything).

A walk through nearby Crawford Market was mandatory to pay homage to the pyramids of pineapples and watermelons before a mid-morning stop at Badshah for falooda (152/156, LT Marg, opposite Crawford Market, +91 22 23421943; around 80p for a falooda). Falooda is a milkshake with a long tradition. It used to be made using ice gathered from the mountain-tops. Today’s incarnation is a tall glass filled with rose syrup, milk, glass noodles, ice-cream and topped with slippery delicious basil seeds. In 40C heat, it was everything I needed in one glass.

Refreshed and in search of the city’s best street food, we took the superhighway north to Bandra – the hipster enclave of Mumbai – and pulled up outside Elco Pani Puri Center. This was no hole in the wall joint, it was discovered by the Bollywood set some time ago. Crispy semolina shells are filled with a mixture of pulses, dunked into a tangy tamarind chutney and then ice-cold mint and coriander water – there you have pani-puri. You have to eat it quick, before it explodes! There’s no other way. It was a vibrant clash of sweet, sour, cold and crunchy: a rollercoaster of flavours. The pani-puri is made with mineral water here, so it’s a safe place to get your fill.

Although dinner options are vast in the city, Shree Thaker Bhojanalay is one of Mahesh and Sam’s go-to vegetarian restaurants (31 Dadisheth Agyari Lane, opposite GT High School, Kalbadevi, +91 22 22069916; around £12 for two thalis). Gujarat, a state on the west coast of India is famous for its thalis: a plate onto which a rainbow of seasonal curries, chutneys and a variety of breads are served. The waiters walked around barefooted hawking our plates ready to top us up until we begged for mercy (just like with any Gujarati mum).

After dinner, we headed to Chowpatty Beach where Mumbai’s young lovers go to hold hands (and escape their parents), while the rest gravitate towards the whizz, pop, bang of the food and entertainment stalls. Ordinarily, I’d have gone to Bachelorr’s across the road for a mango juice or a custard apple ice-cream but I’m only human and I’d hit a wall. You can eat like a queen in Mumbai, for not very much, the only limitation is always the size of one’s tummy.

FIVE MORE GREAT VEGETARIAN FOOD STOPS IN MUMBAI

Bombay Sandwich at Sanjay’s

A tower as big as the average Mumbaiker’s dreams; made up of three layers of bread interspersed with cooked beetroot, potato, fresh tomatoes, peppers, cucumber and a hot layer of mint-chilli chutney, it’s then grilled, layered with cheese and served with a red chutney. It’s a party for your tastebuds.
• Mahatma Gandhi Road, next to Vinod Apparels and Magna Book Store, Fort; sandwich £1.20

Soli’s pav bhaji at Tardeo Junction

Originally a millworker’s meal, this is a rich spiced mash of masala’d vegetables like potatoes, aubergines, peas and tomatoes served with rough bread rolls (pav) doused in hot butter. The best I’ve had is at Soli’s stall, a roadside two-man operation. If Soli’s is closed, Sardar on Tardeo Road, opposite the bus station is also excellent.
• Opposite Haji Ali Juice Centre, outside Heera Panna, around £1 a portion. Note: open 7.30pm to midnight

South Indian food at Dakshinayan

Most Mumbaikers will not look at any other south Indian other than Café Madras in Matunga but Dakshinayan on Malabar Hill is my pick. Its crispy, crunchy and sweet onion masala dosas are a wonder. Its tart tamarind rice and coconut sevai (noodles) are delightful too and take me right back to eating my way around Karanataka and Kerala.
• 183 Teen Batti Road, Walkeshwar, Malabar Hill; around £8 for two

Rice pankis at Swati Snacks

This is a popular pure-vegetarian neighbourhood restaurant in Tardeo serving snacks from Gujarat on the west coast of India. My favourite is the panki, a rice and dill pancake steamed between two banana leaves served with a hot and lemony coriander chutney.
• Karai Estate, opposite Bhatia Hospital, Tardeo, +91 22 6580 8406, swatisnacks.com; panki £2

Paneer tikka at Copper Chimney

The Worli branch of Copper Chimney, for me, is best in show when it comes to north Indian cooking or Mughlai-style cooking. Its rich paneer cheese, coated in yoghurt and garam masalas cooked in the tandoor is divine: slightly charred, addictively savoury and melts-in-the-mouth. Mop it up with a thin roomali (hankerchief) roti before moving onto a vegetable biryani. Beware the portions are big, so come hungry.
• Lotus Court, Ground Floor, Dr AB Road, Worli, +91 22 24925353, copperchimney.in

Meera Sodha is author of Fresh India: 130 Quick, Easy and Delicious Recipes for Every Day (Penguin, £20). To order a copy for £16, including UK p&p, visit the guardian bookshop or call on 0330 333 6846