Belgian Shrimp Croquettes (Croquettes Aux Crevettes Grises)

From Ruth Van Waerebeeks’s “Everybody Eats Well In Belgium Cookbook.” Traditional Belgium shrimp croquettes are made with North Sea shrimp, called brown shrimp — small, and very flavorful, and not readily available in the United States. Ruth writes: “For a while I thought I could never duplicate [the traditional Belgian croquette in the U.S.] …. But with a little experimentation I achieved quite good results. Do avoid frozen peeled shrimp, for they have very little flavor and search out the freshest shrimp you can find.” The dish must be refrigerated at least overnight to allow yourself enough preparation time. (And DO read the directions through to prepare yourself for the time involved!)