Chinese dumplings vegetarian style - mushrooms raw or cooked?

Question

I recently started making Chinese steamed dumplings (Jiaozi) with cabbage and beef mince. In this version I simply mix together all the ingredients for the filling (cabbage, onion, beef) when they're raw, fold the dumplings and steam them for a few minutes.

I've now seen recipes for vegetarian variants, e.g. with mushrooms, tofu and some other vegetables, plus the cabbage. For the mushrooms in particular some recipes suggest frying them in the pan before mixing them together with the rest of the filling. Is this always necessary and if not what are the pros and cons of cooked vs raw mushroom? Is it to drain some liquid first?

Answer 1

Is this always necessary and if not what are the pros and cons of cooked vs raw mushroom?

If you don't fry the mushrooms first, they will turn out rather watery and bland. So yes, you could say it's to drain some water first, though I don't really drain the water; I let the water evaporate.

Answer 2

Mince salt squeeze

That's how Guo Ayi, our nanny, made them for us when we lived in Beijing.

The only cooked ingredient in fillings would be crispy rice.

Salting to wilt also done to some greens like mustard.

Answer 3

You can fry the mushrooms, but the more common thing to do is to just blanch them in boiling water. The other answer says that they'll be watery and bland, but the bigger problem IMO is that earthy flavor which can be taken away by the blanching. Of course, you want to add salt to the blanched mushrooms and press/squeeze them so that excess water comes out; then dispose of the salty water. (The same should be done to other ingredients with high water content, such as napa cabbage and carrots. It's not necessary for drier ingredients such as wood ear fungi.)

Also, if you can find dried shiitake mushrooms, they have a more complex flavor than the fresh ones, so you might want to mix some in. In Chinese cooking, dried shiitake mushrooms are often preferred to fresh ones. You will need to soak them in water (and then squeeze out the excess water), of course, but you won't need to salt them, or to blanch or fry them.