From The Japanese Cooking Class Cookbook. Best with fresh clams, but canned baby clams can be used in a pinch, just don't cook them, as they are already cooked, just marinate them in a few drops of sake. Raw clams may also be used if they are VERY fresh. Place shucked raw clams in a sieve, immerse them in a large bowl containing 3 cups cold water and 2 tsp salt. Gently shake colander several times, allowing water to rinse clams; drain well.