1. Cut the tips off the asparagus and set them aside; remove the inedible part of the asparagus and cut the remaining stalks into thirds.
2. Simmer the asparagus in the stock until tender, about 15 minutes; pour both into a blender and puree until very smooth, 2-3 minutes.
3. Steam or boil the sausages until cooked or warmed; reheat the asparagus sauce; blanch the reserved tips in boiling water 2-3 minutes and drain.
4. Cut the sausages diagonally into 1/2 thick slices; spoon the asparagus sauce into a shallow soup plate, add the sausage and sprinkle with the asparagus tips.