When cooking white clams, use cold water in the pot. This method can ensure that the clams are evenly heated during the heating process and are more delicious. In the process of cooking clams, you can first put seasonings such as onions, ginger and aniseed into cold water, and then put the washed clams into water after the water boils, so as to ensure that the clams bloom evenly and the cooked clams are more tender and sweet. At the same time, pay attention to thorough heating when cooking to avoid the residue of bacteria and parasites. The square horse clam, commonly known as white clam, mud clam and cloth pigeon head, is mostly produced in Liaoning, Shandong and other places, and its meat is delicious. Mainly inhabit the intertidal zone in the middle and lower reaches and shallow mudflats. The shell is thick and slightly quadrangular. The two shells are extremely inflated. The top of the shell protrudes slightly in front of the center of the back edge, and the tip bends forward. The shell is covered with skin, the top is white, the larvae are lavender, and the belly edge is yellow-brown, and the belly edge often has 1 extremely narrow edges. The growth line is obviously thickened, forming uneven concentric rings. The inner surface of the shell is white, and the hinge part is wide. The left shell has a bifurcated main tooth, and the right shell has two main teeth arranged in a figure of eight. The teeth on the front and back sides of the two shells have developed into sheets, the shell on the left is single, and one has two sequins. The external ligament is small and light yellow; The internal ligament is large and yellow-brown. Obturator internus scar is obvious, the former obturator internus scar is slightly smaller and oval, the latter obturator internus scar is slightly larger and nearly round, and the jacket scar is clear and clings to the abdominal edge.