For fondue de poireau : blanch the leek
in salted water for 4 minutes. Drain, cool
in an ice
bath, drain again, and dry on absorbent paper. In the meantime, melt the butter
in a saucepan over medium heat. Add the onions and sweat until tender and lightly colored. Add the cooked leeks, cream
, and pepper
, while stirring constantly, until creamy.