Anjan Chatterjee, who owns the 'Oh! Calcutta' chain of restaurants, seeks to answer this in his book by the same name which is a culinary journey into the Bengali kitchen.
"A part of the answer must be in the uncommon ingredients such as banana flower, the sharp tastes of mustard oil or 'kashundi', and the thrilling tang of Bengal's king of limes, the Gondhoraj 'lebu'," he says.
"Look beneath the surface of royal dishes like 'Mochar Ghonto' (banana flowers with poppy seeds) or 'Aam Achar Ilish' (hilsa cooked with pickled mangoes in pumpkin leaves) and you might be surprised to find a few humble ingredients.
Oh! Calcutta is a dining brand of Speciality Restaurants Limited. It has nine restaurants across India and one in Bangladesh. Its food represents the marriage of Bengali, Nawabi and British cuisines in the city of Kolkata. The restaurant Oh! Calcutta captures the unique cuisine, serving flavours and tastes perfected over generations and its signature recipes find mention in the book, published by Random House India.
"I never dreamed that the dishes I have cooked for the pleasure of so many at home and in my restaurants would one day become a heritage cookbook such as this. Serving my city's glorious cuisines to Indian diners has taught me one thing - there is a little bit of Kolkata in everyone," he says.