Never buy them ground - this aromatic oil is fugitive. True cinnamon, native to Sri Lanka and Kerala, is a milder, sweeter and more delicate spice than cassia. Cassia, originating in Burma is pungent and peppery and less expensive than the tightly curled quills of true cinnamon, it is more suitable for savoury dishes than sweet. In fact, cinnamon is rarely if ever used in Indian sweets, although in Mexico and South America it is more popular than vanilla. In Mexico, cinnamon's preservative effects are much appreciated in breads and cakes and ancient heavily spiced cakes such as the Tuscan panforte are living fossils of an era when spices were used to preserve as well as to flavour - as they are still in India.
Chillies are potent and famous.
They contain six to nine times the vitamin C of tomatoes. The seeds are often used as a separate spice in Asia, when the whiteness of a dish is desirable. The smokiest-flavoured chilli powder is made by roasting dried red chillies in a pan until they darken, become crisp and smoke slightly, then grinding them, with the seeds. Their pungent taste and flowery aroma is essential to garam masala, Mogul meat dishes, pulaos and onion-tomato sauces, as well as for perfuming the tempering oil in Rajput dishes. Cloves are also used in sweet dishes - in one pastry dish, milk is simmered slowly until reduced to cheese, then wrapped in a triangle of filo and fastened with a clove before deep frying.