Cumin

Buy cumin whole, as small seeds, and keep it that way until the moment you cook. Grind it yourself, or just crush it under a knife — a handful of whole seeds in the jar will outlast a spoonful of powder sitting there losing its voice.

Choose it with your fingers and your nose. Rub a few seeds in your palm: good cumin smells warm, a little sharp, almost peppery, with that deep earthy pull that fills the kitchen before the pan even gets hot. If what you smell is flat and dusty, put the jar back.

Some people say cumin and caraway are the same spice under two names. No! Stand them side by side and your nose tells you right away — caraway is sweeter, closer to anise; cumin is darker, heavier, more stubborn. Confuse them and your pilaf or your chili comes out tasting like rye bread, not like a proper pot of meat and onions.

Toast whole cumin in a dry pan before it goes into the dish. Watch the color deepen just a shade, listen for the seeds to start ticking against the metal, and wait for that nutty smell to rise — that is the only sign you need.