All types of coriander--whole, ground, and the leaves--have many uses. Whole coriander seeds are used in pickling and for special drinks, such as mulled wine, whereas ground coriander is often used in baked goods (especially Scandinavian), curry blends, and soups. Ground coriander is a major component of garam masala, a basic spice mixture used in Indian and Pakistani cuisine.
Ground coriander quickly loses its pleasantly sweet taste and smell. When a recipe calls for ground coriander, it's best to grind whole seeds just prior to use. To heighten the flavor of coriander, first toast the whole or ground seeds.
Cilantro leaves are widely used in the cuisines of India, Mexico, the Orient, and the Caribbean. The fresh herb may be used like parsley, both as a garnish and a flavoring. Fresh coriander is what gives many fresh salsas and ethnic dishes their zing. Use it sparingly with delicate ingredients, or its flavor overpowers. In strongly flavored sauces and salsas, it can be used in larger quantities. For best flavor, the leaves should not be overcooked.
Despite their differences, all forms of coriander blend well with garlic, cumin, oregano, onions, ginger, and chile peppers.