Mayonnaise: Japanese borrowed from the French and made mayonnaise their own. Mayonnaise is used in some sushi preparations and as a condiment for savory omelets (okonomiyaki).
Miso: Miso is a very important flavoring ingredient in Japanese cooking, added to soups, sauces, marinades, dips, salads and main dishes, and provided as a table condiment. It is made from cooked grains (rice, barley or soybeans) that are fermented with a starter. It is then mixed with ground soybeans and aged in barrels for months or even years. Miso paste's depth of flavor comes from its yeasts and lactic acid bacteria: in general, the darker the miso, the stronger the flavor. Miso paste should be stored in the refrigerator.
Sesame seeds: Mild and nut-like, sesame seeds are used to add texture and flavor to a variety of Japanese dishes. Their flavor intensifies when toasted.
Daikon: A large root with a sweet flavor and crisp texture, daikon are used in salads, in stir-fries, and pickled as a garnish.
Japanese Cucumbers: These long, thin cucumbers have thick skins that sport tiny bumps all over them. They are crisp and relatively seedless. Japanese cucumbers originated in the Himalayan region.
Ginger: Ginger made its way to Japan via China many centuries ago. Slivered or sliced thin, ginger is frequently added to Japanese stir-fries, salads and soups. Store leftover ginger root in the refrigerator wrapped in plastic wrap. Pickled ginger--paper-thin pink slices--is traditionally eaten with sushi. Because of its antiseptic qualities, pickled ginger is thought to combat potential food-borne bacteria.
Shiitake mushrooms: Fresh shiitake mushrooms are grilled or served in soups and stir-fries. Dried shiitakes are more flavorful and should be brought back to life in a soak of warm water. Add the soaking liquid to soups and stir-fries.
Enoki mushrooms: Looking a bit like a handful of long white carpentry nails, enoki mushrooms grow in clumps; they have a slightly crunchy texture and mild flavor. Use them in salads or added to soups and other hot dishes at the end of cooking.
Japanese eggplant: Smaller and thinner than European eggplants, Japanese varieties have thin skins and a delicate flavor.