Xiao Hei Hao Qing is a small Cantonese restaurant on the Dingxi Lu strip specializing in grilled oysters, scallops, and other varieties of shellfish. Their beer chicken and black pepper noodles come highly recommended. It's immensely popular with the locals and tables fill up fast (it is easier to get a table after midnight). Either get there early or book ahead. Highly recommended. They may not have an English sign, so look for the cartoon of the cute little black cat.