A hugelculture bed seems like it would be the ideal way to get mushrooms growing next to your garden plants. Most cultivated species of mushrooms grow on wood, so if the logs used in constructing a hugelculture bed were inoculated with edible mushroom spawn, the mushroom mycelium would help digest the logs and provide delicious mushrooms... I hope one day to be in a situation where I can try this.
Historically, farmers have grown Wine Cap Mushrooms (
Stropharia rugosoannulata) in bales or piles of straw in between rows of other crops in Central Europe. (Wine caps and Shaggy Manes prefer
compost to wood, sometimes referred to as secondary decomposers vs. the primary decomposers that eat wood directly.)
As with gathering wild mushrooms, care must be taken in identification, since many poisonous mushrooms also grow on logs. Just because one is trying to grow edible mushrooms doesn't mean that poisonous ones won't also come up.