The name Shimeji can actually refer to various species of mushrooms which explains the differences in appearance you can find - some can have a more "traditional" mushroom shape with a bulbous cap, while the ones I'm using have a more trumpet-like shape.
They are sold in clumps, which I can better explain by way of a photo
You can see the shimeji of various sizes all beginning from the one solid base. To use, it's just a matter of trimming off this hard base and then dividing the mushroom into there individual units.
With this type of mushroom I like to keep it simple - so I've made a quick and easy Mushroom Tart.
[Makes 1x13cm/5" tart]
fresh thyme leaves
1 garlic clove, crushed
⅓ cup milk
sea salt and white pepper
Make the filling:
Prepare the mushrooms by cutting away the hard base. Separate it into smaller clumps and then cut into individual mushrooms.
Heat a knob of butter and a little oil in a skillet over a medium heat - when the butter has melted, add in the prepared shimeji along with the fresh thyme leaves and garlic. Cook quickly until lightly golden and then set to one side. Season with a little sea salt and white pepper.
Make the tart:
Line a 13cm/5" tart with pastry - lightly prick the base and cover with baking paper and beans. Bake in a preheated 160°C for 5 minutes - remove the paper and the beans and then cook until the base appears dry.
Spread the mushrooms over the base and then dot with a little bocconcini - depending on the size, just tear the bocconcini roughly.
Whisk the egg and milk together and then pour over the filling.
Return the tart to the oven and cook until the pastry is golden and the filling has set. The filling will puff up while cooking but will flatten out as it cools.