Chop mushrooms, garlic and shallot then set aside.
Add the olive oil to the saucepan or skillet and put the heat on medium. When it is hot throw in the mushrooms and cook for 3-5 minutes until brown. Keep your eye on them and stir occasionally.
Add the garlic and the shallot for another minute or so and stir together.
In the meantime, measure the flour and set aside. Then boil the kettle and measure out 1 cup of hot water. Add the stock cube and give it a good stir so that there are no lumps.
To make the roux, add the white wine to the vegetables and then add the flour slowly. The mixture will become clumpy and then slowly whilst stirring the flour and vegetable mix add in the vegetable stock. Once the stock has been absorbed add the milk slowly. Be sure to whisk out all the lumps in the mixture and then turn the heat down low.
Add the nutmeg, salt, and black pepper and cook for a further 5 minutes on a low heat whisking continuously. If you want to add nutritional yeast to the recipe then do it now.