Purée of Portabello Mushroom Soup

Clean and roughly chop the portabello mushrooms, and finely dice the leeks, celery, onion, and garlic to prepare all aromatics before cooking.

In a large heavy-bottomed pot, melt the butter with the olive oil over medium heat, then add the leeks, celery, and onion and sauté until softened and translucent.

Add the garlic and thyme leaves to the pot and cook, stirring frequently, until fragrant.

Add the chopped portabello mushrooms to the pot and sauté over medium-high heat until they release their moisture and begin to brown.

Deglaze the pot with the sherry, scraping up any browned bits from the bottom, and allow the alcohol to cook off.

Pour in the vegetable stock, bring the soup to a boil, then reduce the heat and simmer until all vegetables are completely tender.

Remove the pot from the heat and use an immersion blender, or transfer in batches to a standing blender, to purée the soup until completely smooth and velvety.

Season generously with salt and freshly ground black pepper, ladle into warm bowls, and finish each serving with a grating of parmesan cheese.