Melt the butter in a saucepan over medium heat. Add the onion and celery and cook, stirring often, until soft but not brown. Add the stock and bring to a boil. Add the asparagus; simmer for 5 minutes.
Add salt, pepper, and mace. Remove from heat. Slowly stir in the cream. Reheat gently. Serve in bowls garnished with hard-cooked egg.
Servings: 6