Asafoetida does taste vaguely like onions and garlic, and is used in Indian cookery for those strict Hindus who will not eat onions or garlic for religious reasons. However, it has some flavour notes which identify it as a seriously Asian spice, and I would not put it into a paella. It'd be akin to covering your pizza with ketchup instead of tomato salsa.a small pinch asafoetida (I can never spell that) has the onion flavour without the stomach ache.