In Chinese, dried shrimp are called xia mi, which literally means shrimp rice, because small shrimp are sun dried resulting in even tinier pieces of dried shrimp. While they are bigger than grains of rice, most dried shrimp are relatively small. There is some variation in size and the bigger the shrimp, the higher the price. The shells are left on because the shrimp are small enough that they don't pose a problem after drying. The shrimp on the left is a bag that I purchased from my local Asian market. The shrimp in the container on the right is my special, super duper, extra large dried shrimp meat that I get from Steven's mom. She gets them imported from Malaysia because you can't find such large dried shrimp here.
Dried shrimp can smell quite fishy but they pack an amazing umami flavor, xian wei. In Chinese cooking, they're used in stir fries, braises, soups, stuffing, and dumpling fillings.
You can find dried shrimp in most Asian markets. Ideally they should be kept refrigerated even if they're unopened. Often times, I find that the storage policies in some markets are a little lax so they can be found in either a refrigerated aisle or at room temperature. Store them in the fridge when you get home just to be safe (but don't worry my parents and grandparents keep it at room temp, I mean it is dried after all, I'm just paranoid). Since the flavor is so concentrated, a little goes a long way. I only use a spoonful or two at a time. Before cooking, soak the shrimp in some hot water. Many people save this water to add back into soups, but I discard it because I think of it as washing the shrimp. Do not leave the shrimp soaking for too long, otherwise all the delicious umami flavor will leech out.
Recipes:
Recently I used these little dried shrimp in Pim's Pad Thai recipe.
I also use them in green bean stir fry and Chinese daikon cake.