Clean and chop mushrooms (set aside a few whole leaves to use for garnish).
In a heavy pot, saute onions in butter, add mushrooms and salt and pepper. Let cook until the liquids have released and the mushrooms are soft. (About 10-15 minutes).
Mix in the flour, then add in the wine for about 1-2 minutes.
Stir in the chicken broth and let come to a boil. Continue to stir until the flour dissolves into a "roux."
Reduce heat to simmer about 20 minutes.
Transfer half to a blender or food processor to puree and return to pot.
Stir in heavy cream and season to taste with salt and pepper.
Fry the remaining oyster mushrooms in butter to use as a topping and sprinkle with fresh parsley.
Recipe by Liz's Kitchen at https://www.lizbokisch.com/foraging-for-oyster-mushrooms-in-humboldt-county