Dried mushrooms are a quick way to add flavour depth to any dish, especially soups, stews and sauces. They already bring a lot of oomph on their own, but you can add even more flavour when cooking with dried mushrooms by changing what liquid you rehydrate them in.
Image from pollobarca.
Most of us just throw dried mushrooms into hot water, cover them (so they rehydrate faster), and wait for the water to be absorbed. That's fine -- you end up with a tasty, mushroom infused liquid that we can use as a stock base -- but if you swap the water for stock or wine, you can make something with a much richer flavour.The mushrooms gain more flavour from the wine or stock and you also get a mushroom-infused stock mixture that you can either use in your current dish or save for another time. I recommend heating the stock up before adding in the mushrooms as it will make them rehydrate faster. For the same reason, if you're using white wine, try to bring it to room temperature before soaking the mushrooms.