Hoisin Sauce

Let me tell you about Hoisin Sauce, and why it behaves the way it does in a wok.

It's a soybean sauce, thick, dark, almost glossy, somewhere between sweet and salty with a pungent, fermented backbone. That thickness means it clings to meat and vegetables under high heat instead of running off like a thin soy sauce would. That's why it's so good brushed on at the very end of stir-frying, or used in a marinade: it sits on the surface, caramelizes a little, and leaves the ingredient with a sticky, shiny glaze.

Choose it by look and smell, nothing else. Good Hoisin Sauce is deep brown, almost mahogany, smooth when you stir it. Smell it — it should be rich, slightly sweet, with a touch of fermented soy and a gentle tang rather than a harsh one.

Some people say Hoisin Sauce is just sweet soy sauce with spices. No! It's thicker, sweeter, more aromatic, almost jammy, nothing like the thin, sharp saltiness of soy sauce. That mistake leads people to double up on soy sauce "for flavor" and drown the dish in salt, losing the very balance Hoisin Sauce was there to provide.