Potato Leek & Mushroom Soup

Place potatoes, leeks, celery, carrots, mushrooms, butter, and salt in a pot, and cook over medium heat, stirring until the butter is melted and the vegetables are coated.

Add vegetable stock, bring to a boil, cover, and reduce heat to a simmer. Cook until the potaotes are tender (20-30 minutes).

When the potatoes are tender, remove the pan from the heat and puree it's contents with the milk, using an immersion blender, or food processor. Make sure the mixture is absolutely smooth.

Return to pot, add thyme, if using, and pepper. Check if you need more salt. Heat soup gently, until just hot, and serve.