Heat 1 tablespoon oil in a wok or large nonstick skillet over high heat. Add shrimp and cook, stirring, until pink and beginning to curl, about 1 minute. Transfer the shrimp to a plate (it will finish cooking later).
Heat the remaining 1 tablespoon oil in the pan over high heat. Add snow peas, shiitakes and ginger and cook, stirring occasionally, until the vegetables are softened, 5 to 7 minutes.
Meanwhile, whisk sherry, hoisin, soy sauce, cornstarch and pepper in a small bowl.
Stir bean sprouts, the cooked shrimp and the sherry mixture into the snow pea mixture and cook, stirring constantly, until the sauce is slightly thickened and the shrimp are cooked through, 1 to 2 minutes.
Ingredient notes 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 with soybeans and a complex mix of spices. Look for it in the Chinese section of your supermarket, and in Asian markets.