Recipe courtesy Carlo Rota.This recipe is one from Carlo’s parents. This mushroom soup was served at both of his father’s restaurants. It’s also a big family favourite.
To make to bechamel: start by adding butter to a large heavy bottomed pot over medium high heat then sift flour into butter and stir. Once flour becomes pasty. Slowly add milk that has been brought just to the boil. Continue to stir until comes to a boil and thickens, about 5 to 10 minutes. Add nutmeg. Season with salt and pepper. Set bechamel aside.
Add mushrooms to a food processor in batches. Process until finely chopped.
Heat up skillet with olive oil over medium heat. Add onions, garlic and thyme. Let cook until soft and golden. Add mushrooms and toss. Season with salt and pepper. When mushrooms start to release their juices, add the béchamel. Let simmer for about 10 to 15 minutes on low heat. This is the base of the soup. You can refrigerate at this stage.
To finish the soup, add whipping cream to base. Let soup heat through. Mix with a wooden spoon. Serve hot in bowl. Garnish with parsley.