Heat up the butter and the oil in a medium pan and cook the garlic and onions until they're soft but not browned. This should take five to six minutes.
The next step is to add the mushrooms, and cook over a high heat for 3 minutes whilst stirring constantly.
Sprinkle the flour over the mushrooms, mix well to combine.
Stir in the flour and mix well, making sure all the mushrooms are well coated
Pour in the hot chicken stock and bring to the boil.
Add the bay leaf and simmer for 10 minutes
Add the cream , Salt and the black pepper to the mixture .
Remove the bay leaf and leave the soup to cool for a few minutes.
Place the soup in a food processor or if you have a hand blender this is much easier to use.Blend well till smooth, it may be necessary to do this in two batches.
Serve it :)