Notes: Sherry is a type of fortified wine originally from southern Spain. Don't use the “cooking sherry” sold in many supermarkets--it can be surprisingly high in sodium. Instead, purchase dry sherry that's sold with other fortified wines in your wine or liquor store.
Hoisin sauce is a dark brown, thick, spicy-sweet sauce made from soybeans and a complex mix of spices. Look for it in the Asian section of your supermarket and in Asian markets.
Seitan, a high-protein product made from wheat gluten, has a meaty texture and is found in health-food stores or large supermarkets near the tofu. The package weight varies, depending on whether water weight is included. Look for the “drained weight” on the label.