Cook the asparagus in enough stock to cover over medium heat until tender. Puree with an immersion blender, or in batches in a blender.
Melt the butter in your favorite soup pot, and blend in flour to make a roux. Stir in the cream and bring to a simmer over low heat, stirring constantly for about 3 minutes to thicken.
Stir in the asparagus puree and the remaining chicken stock, and simmer for another few minutes. Adjust seasoning to taste.
Serve hot or cold, garnished with a couple of asparagus tips.