and cut the celeriac into roughly 1-inch/2.5 cm pieces. Put the milk
, lemon juice
, and bay leaf
in a large pot, pour over 8-cups/2 liters water. Add the salt, bring to a boil, and simmer
until the celeriac is very tender.
, reserving 1 cup/250 ml of the liquid. Remove the bay leaf. Stir the butter
into the celeriac, then puree until very smooth in a blender
, adding as much of the reserved cooking liquid as needed to achieve a soft, smooth consistency. Season with pepper and salt, and serve.