The coriander plant whose leaves are used so often in Chinese cuisines also gives us small, roundish, tan-coloured fruits that are usually referred to as seeds. The leaves and seeds have very different flavours; the plant is strong and distinct, while the seeds are milder, with a warm, faintly citrusy taste.
Dried coriander seeds are used as a spice in European and Asian cuisines (by contrast, the herb isn't that common in European cooking). The ground spice loses its flavour quickly, so it's better to buy the seeds whole and grind them when needed. The seeds are usually toasted before being used; doing so brings out the fragrance and flavour. Whole coriander seeds are often an ingredient in commercial pickling spices, along with other spices such as caraway, dill and pepper. Coriander seeds are also made into essential oil that's used for digestive and sleep problems.
Coriander seeds are used in spice mixtures for baked goods, such as pain d'epices and lebkuchen. For savoury dishes, their mild flavour works well with everything from fish to meats. Grind the coriander seeds with fennel seeds and combine with grated lemon zest, finely minced garlic, chopped parsley, some paprika, salt, ground pepper and olive oil and rub over pork chops. Sear in a hot skillet then serve.