Start by chopping the shallot.
Add 2 tablespoon of butter to a medium-large skillet and melt then add the shallot and sweat them for 2 minutes. Making sure to keep stirring to help with even cooking.
Next, add in all of the mushrooms and cook them for 6 to 7 minutes. You will notice the mushrooms will give off their water and reduce in size.
Once the mushrooms have reduced in size and given off their water, add in the thyme & a pinch of salt. The salt helps start the flavor party. You'll still need to add the main salt at the end to taste season and adjust to perfection.
Next, add in half a stick of butter and melt, once melted add in 2 tablespoon of all-purpose flour. The flour and butter become a Roux that will thicken the soup. Cook for 2 minutes
Add the cooked mushrooms into a blender or food processor, plus the crab stock. Blend until smooth.
Now taste the soup. Does it need salt? Is it perfect? The chicken stock has a level of salt that may result in you not needing to add any more salt.
You could add some heavy cream to help smoothen out the soup. I did not add any myself as we all agreed it did not need any. Which is very cool for people that are lactose intolerant.