3tbspunsalted butter, softened (plus more for the topping, if desired)
¼ cupheavy cream
freshly ground black pepper, to taste
fresh chives, chopped (for garnish)
Instructions
In a large pot, combine the celery root cubes, potatoes, chopped leek (white and green parts), Maldon salt, milk and chicken stock. Place the pot over medium-high heat and bring it to a boil. Once boiling, reduce the heat to a simmer, cover the pot, and cook for about 15-20 minutes, or until the celery root and potatoes are tender when pierced with a fork.
Once the vegetables are cooked, drain them, reserving some of the cooking liquid. You can use this liquid later to adjust the consistency of the puree.
Transfer the vegetables to food processor and puree them with butter until they have a smooth consistency. Transfer back the pureéd vegetable to the pot. Gradually add the heavy cream to the vegetable mixture while stirring until you achieve the desired consistency. If the puree is too thick, you can thin it out with some of the reserved cooking liquid. Season the puree with salt and freshly ground black pepper to taste.
Transfer to a serving dish. If desired, top it with a piece of butter and garnish with chopped fresh chives.