4 ideas
In Kashmir, Hindu Pandits and Muslims cook largely the same mutton and use the same local spices, yet their cuisines are distinct. Pandit cooking leaves out onion and garlic and relies on asafoetida, dried ginger, fennel and yogurt. The case shows religious boundaries being maintained through small, deliberate choices of flavoring rather than through different staple foods.
The underlying techniques, souring agents, spice pastes and regional ingredients largely stayed the same. A converted community's cuisine therefore records both the new faith, in its meats, and the older local identity, in its methods.
Groups barred from certain foods, such as Bengali Hindu widows forbidden fish, meat, onion and garlic, did not simply eat less well. They built elaborate vegetarian repertoires from peels, stems, flowers and lentils. A prohibition narrows the available ingredients but pushes the cook to get more out of what is left, which produces whole sub-cuisines.
Such communities hold on to signature dishes as markers of identity, while quietly substituting ingredients the new place lacks. Their cooking is therefore both more insistent on tradition and more improvised than the original.