It's a British national dish.

https://en.wikipedia.org/wiki/Chicken_tikka_masala

Have you read the article you linked?

Chicken tikka masala is chicken tikka, chunks of chicken marinated in spices and yogurt, that is then baked in a tandoor oven

Those don't sound like British words... let's follow the links:

Chicken tikka is a chicken dish originating in South Asia.

A masala is any of the many spice mixes used in Indian cuisine. The name comes from the Hindi word for spice.

The tandoor is used for cooking in Southern, Central and Western Asia.

Did you mean British commonwealth, or British isles?

So? Tomatoes aren't Italian, but pizza is.

Nobody is disputing the Asian influence on British cuisine. And nobody is disputing whether or not tikka masala is British.

Have you?

"...The historians of ethnic food Peter and Colleen Grove discuss various origin-claims of chicken tikka masala, concluding that the dish "was most certainly invented in Britain, probably by a Bangladeshi chef".[14] They suggest that "the shape of things to come may have been a recipe for Shahi Chicken Masala in Mrs Balbir Singh’s Indian Cookery published in 1961".[14]..."

From earlier in the same section: "The origin of the dish is disputed. One explanation is that it originated in an Indian restaurant in the United Kingdom,[3][7] but probably from the British Bangladeshi community which ran most Indian restaurants in Britain.[7] Rahul Verma, a Delhi expert on street food, offered a different explanation, speculating in 2009 that the dish may have originated—probably by accident with subsequent improvisations—in the Punjab and Uttar Pradesh during the last 50 years.[1]"

Its an adaptation of Indian cooking to British tastes developed fairly recently historically (different stories point to different origins either in Britain or in India during the British Raj or within a couple decades of its end.)

I'm reasonably sure that peruvian people knew the concept of putting a potato in the fire much before british "invented it".