Chicken tikka masala played that role in the UK. Different enough to be interesting, but easy enough for new diners to appreciate.
Saag paneer has played this role in the USA. It’s similar to creamed spinach, an American staple, and uses cheese, which adds familiarity, but Indian spicing makes it interesting.
According to Lenore Newman, in her book Speaking in Cod’s Tongues, which tries to identify what Canadian cuisine means, the breakthrough Indian-Canadian dish might be blueberry lassi.
Newman argues that Canada’s cuisine is a creole, like a language formed by blending different ones. It is “a recipe from elsewhere reimagined with Canadian ingredients or a Canadian recipe reimagined with ingredients from elsewhere”.
Blueberry lassi is an example of the former — 100 million pounds of blueberries are grown in the Fraser River basin near Vancouver, where Newman samples the lassi.
Butter chicken poutine is an example of the latter, where the iconic Quebec dish of French fries mixed with fresh cheese curds is reimagined with the mild Indian curry substituting the cheese.
It seems natural that Canadians would claim two Indian dishes, one nominally from a French-speaking part of the country. Any survey of Canada must deal with its divided history between French and English cultures.
But Newman suggests that more than the divide, the constant tussle has prevented development of a single assertive national identity. And while this can be seen as a problem — Canada’s famous blandness — it could also be an opportunity to create a new kind of identity, driven by all the streams of immigration to the country.
Newman argues persuasively for how this is happening with dishes like perogies (dumplings from Poland or Ukraine)