Litti chokha have been my own favourite street snack for a long time, and I have always found the best versions at Nimtala Ghat Street in North Kolkata, a chaotic 1km stretch near the banks of River Hooghly. Here, street shacks rustle up endless tiny littis, flipping them on a tawaa (a flat, metal cooking pan) over a coal or wood fire. At Rs 40 (£0.43), every portion consists of five or six litti balls and a side of chokha (roasted vegetables like eggplant, tomatoes and potatoes). A tangy chutney of green chillies, tamarind, mint leaves and wispy shreds of garlic completes the flavour profile.

"But things have changed a lot over the last few years," said Pankaj Mishra, co-owner of The Litti King, a small restaurant specialising in Bihari cuisine in an upscale neighbourhood of South Kolkata. "When we opened our t in 2016, we did not imagine that litti chokha and sattu sherbet would be so popular among the well-heeled." Both items now feature on menus for upmarket wedding and plush poolside parties. "Some of the city's top industrialists are our regular patrons," Mishra said.

Food studies professor Ray had an idea as to why. "The new panic about health among elites – associated with over-consumption of junk food and sedentary lifestyles – is now accentuated by Covid and has set them on the pursuit of 'superfoods'," he said. "This is where sattu has come in with its putative protein and micro-nutrient content."

The health-conscious across Indian metros such as Delhi and Bangalore are also discovering the delights of sattu in high-end restaurants, where chefs are adding contemporary spins to the rustic recipes by incorporating grated cheese to the dough or lending a tangy twist with pickles. The trend has caught on in gourmet stores too, where sattu is offered in fancy packaging starting from Rs 190 (about £2) per kg, which is about 2.5 times costlier than the time-tested varieties used in the street stalls.

"There has been an unprecedented rise in sale of sattu packets in recent months," said Sayoni Samanta, a saleswoman at a South Kolkata outlet of Spencer's, a pan-Indian retail chain. "I think the customers are preferring those products that come with organic and gluten-free labels," she added.

Dr Tulasi Srinivas, a professor of anthropology at Emerson College in Boston, said, "Transformation of dishes like sattu are a kind of elite cultural appropriation and gentrification. For the elite, it's a voyage of discovery whereby they can demonstrate their culinary knowledge of something healthy and 'exotic'. It also works well for the marketers of these 'superfoods'. But what I am glad about is that it is a healthy local food that is getting rediscovered and mainstreamed." 

I saw that for myself at Baati Chokha, a fine-dining establishment specialising in Purvanchali (Bihar and Eastern Uttar Pradesh) and North Indian cuisine, located in Salt Lake, Kolkata's preeminent IT hub. On that weekday night at around 22:00, most of the tables were occupied by young office workers. At a table near me, Deepika – an employee at an infotainment firm in the neighbourhood – was fiddling with her phone and taking small, occasional helpings of litti chokha, artfully plated in front of her.

"I come here often for a late-night snack during my breaks," she said, pointing to her half-finished plate. "This was not something I grew up with, so bit of an acquired taste for me. But now I love the earthy flavour of these sattu-filled discs. Easy on my stomach but filling enough to see me through my night shifts. And importantly, its low glycaemic index means no guilt pangs, as was often the case with the junk bites I used to gorge on," she added with a smile.  

A few days later, I went back to Yadav's sattu stall to see how felt about his unpretentious street staple going upscale. On that sweltering June afternoon, it was business as usual for him, and he did not seem too interested in sattu's emerging trendiness. “As long as I can provide my customers their glass of sherbet at Rs. 10 [£0.11], I am happy. I only hope all this hullabaloo does not shoot up the prices,” he said. Lallu, a middle-aged cart puller, stood nearby listening attentively. He finished his drink, murmured in agreement and went back to pull his loaded cart from the side of the kiosk on to the busy streets of Kolkata.

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