This cousin of ginger is prized in Thai cusine for its extraordinary citrus-like flavor in soups and its burst of herbal heat in curry pastes. In its fresh form, its color ranges from delicate ivory to warm brown, depending on its exact variety and age. Round and plump with lots of thumb-like protrusions, it's always encircled with dark rings along the rounded chunks.
Fresh ginger root, though it doesn't have the same flavor nuances as galangal, can be substituted it in a pinch.
Fresh galangal can be found at many Asian grocery stores. You may also find dried galangal in large, woody-looking slices. These work wonderfully in many Thai dishes (see prep below for how to use them). Avoid dried galangal powder, which lacks the intense aroma and flavor of fresh.
To infuse a soup, galangal is usually sliced unpeeled. For curry pastes, it's peeled and chopped, then ground with the other paste ingredients.
To prep dried galangal, soak the slices in warm water for 20 to 30 minutes until pliable before using.
Store fresh galangal loosely wrapped in plastic in the refrigerator for five to seven days. Or slice it thinly, arrange the slices in a single layer in a zip-top plastic bag, press out the air, seal tightly and freeze for up to six weeks (use frozen galangal slices without thawing them).