It's obvious that the straw mushroom doesn't get its name from its shape, which is round rather than long, thin and straw-like. Rather, the fungus is named because it's grown on beds of straw. The first time I saw specimens being sold by a wet-market vendor, I didn't recognise them as mushrooms because they didn't appear to have a cap and a stem - it wasn't until I cut one open that it became recognisable.
Usually (in Asia, anyway), the straw mushroom is picked when young, at what mushroom growers call the "egg phase", which is before the cap and stem burst out of their surrounding, edible veil. If left to mature, straw mushrooms look almost like comic-book versions of fungi, with their brown caps tightly closed over thick stems. Straw mushrooms are sold in cans but they're not worth buying.
Fresh straw mushrooms, which are used in many Asian cuisines, have a dense, meaty, slippery texture. Their flavour isn't all that distinctive but, like other types of mushroom, they soak up the taste of whatever other ingredients they're cooked with.
For a simple stir-fry, cut the mushrooms in half lengthwise. Heat some oil in a wok, add a sliced clove of garlic and stir. Add the mushrooms and season them with oyster sauce, rice wine and ground white pepper. The mushrooms will give off some liquid but, if left to simmer, will re-absorb it. When this happens, scoop the ingredients out of the wok and serve over a bed of lettuce that's been blanched in lightly salted boiling water then drained.