Gentse Waterzooi de légumes: delicate creamy Ghent stew of leeks, carrots, celeriac, and waxy potatoes simmered in vegetable broth, finished with an egg yolk and cream liaison and fresh herbs.
Melt the butter in a heavy soup pot over medium heat. Sauté the leeks, carrots, and celeriac batons for 5 minutes without browning.
Add the halved potatoes and pour in the hot vegetable stock. Bring to a boil, reduce heat, cover, and simmer for 20 minutes until the vegetables and potatoes are tender.
Whisk a ladleful of the hot broth into the egg yolks and cream mixture to temper, then pour the mixture slowly back into the simmering pot while stirring constantly (do not let boil).
Simmer gently for 2 minutes until silky and velvety. Season with white pepper and salt, ladle into deep warmed bowls, scatter with fresh chervil, and serve with crusty sourdough bread.