The death of a Pakistani-Scottish chef who claimed he cooked up the world's first chicken tikka masala is prompting a flood of tributes to what's been described as 'Britain's national dish' — and reviving a debate into its true origin.

Ali Ahmed Aslam, known widely as Mr. Ali, died of health complications on Monday at age 77, his nephew Andleeb Ahmed confirmed to NPR.

Aslam was the owner of Glasgow's popular Shish Mahal restaurant, which he opened in 1964 after immigrating from Pakistan as a boy.

In his telling, Aslam devised the globally beloved recipe one night in the 1970s, when a customer complained that traditional chicken tikka was too dry. The chef went back to the kitchen and combined spices, cream and a can of condensed tomato soup. Voilà: the modern model for chicken tikka masala was born.

But so, too, was a debate about its origin.

Who created chicken tikka masala?

In 2009, a Glasgow politician campaigned for chicken tikka masala to be granted protected heritage status and for the city to be named its official home. But the bid was rejected after multiple establishments from around the U.K. laid claim to the dish.

Others say the curry was most certainly invented in South Asia. Monish Gurjal, the head of the popular Indian restaurant chain Moti Mahal, says his grandfather was serving chicken tikka masala to Indian heads of state as early as 1947.

"It's kind of like: who invented chicken noodle soup?" says Leena Trivedi-Grenier, a freelance food writer who probed the various origin claims in 2017. "It's a dish that could've been invented by any number of people at the same time."

Chicken tikka (sans the masala) has been a popular street food in Pakistan and northern India for decades. At its core, it involves chicken that's marinated in chili powder and yogurt, then blackened on a grill or in a tandoor, an oven made out of ground clay.

The cooking method leaves chicken tikka prone to drying out, says Trivedi-Grenier; the idea to add a sauce with staples like cream, butter and tomato isn't too revolutionary.

Another point of debate is the dish's relatively mild taste. In an interview originally shared by AFP news, Aslam said the recipe was adapted from traditional cuisine "according to our customer's taste."

"Usually they don't take hot curry," he said of U.K. diners. "That's why we cook it with yogurt and cream."

In 2001, the U.K.'s foreign secretary, Robin Cook, said in a speech that chicken tikka masala is a "a true British national dish," epitomizing "multiculturalism as a positive force for our economy and society."

But to Trivedi-Grenier, the idea that chicken tikka masala was created solely to suit British people's palates is "garish" when one considers the symbolism.

"How do you colonize and enslave an entire country for a century and then claim that one of their dishes is from your own country?"

Customers remember Aslam as a humble man and talented chef

Aslam, a man who shied away from attention, found a sense of purpose in exposing his customers to new flavors, said his nephew, Andleeb Ahmed.

"He was actually serving customers until the end of his life," Ahmed said. "That was his passion. That was what he loved doing."

Around the world, those who've dined at Shish Mahal are remembering Aslam as kind and talented, and someone who helped expand their culinary sensibilities.

"I tasted my first curry in the Shish Mahal in 1967 and continued to enjoy them during my student days and beyond," tweeted a former Scottish member of parliament.

Vijay Prashad, an international journalist, wrote that, to say the addition of chicken tikka masala has benefited many menus, is "controversial," but the food is undeniably good.

"Naans down in [Aslam's] honor," he added.

Ironically, when it came to his own taste preferences, Aslam ranked chicken tikka masala fairly low, his nephew said.

"The chefs would make a very traditional curry for him. He'd eat it at lunch every day," Ahmed explained.

"He'd only have chicken tikka masala when guests were over."