Source: Libro di cucina del secolo XIV, 14th century.
Fungi di Monte
Toglie fungi di monte, e lessali: e gittatene via l’acquaa, mettili poi a friggere con cipolla tritata minuto, o con bianco di porro, spezie e sale e dà a mangiare..
Translation: (from The Medieval Kitchen: Recipes from France and Italy)
Mountain MushroomsTake mountain mushroom and boil them; and discard the water; then fry them with finely sliced onion, or with white of leek, spices, and salt, and serve.
Quarter and parboil mushrooms and drain. Slice onion and sauté mushrooms, onions, spices and salt until onions are translucent and serve.
I like to use a combination of the Brown Crimini & White Button mushrooms for this dish. I have yet to determine what variety of mushrooms are inferred by "Mountain Mushroom".
A variation on this recipe is substituting a couple cloves of minced garlic for the onion. I did this variation for a feast for the Principality of the Mists Fall Investiture in 2003.
The Medieval Kitchen: Recipes from France and Italy; Odile Redon, Françoise Sabban, & Silvano Serventi, translated to the English by Edward Schneider; The University of Chicago Press, 1998