Peel the asparagus and cut off the ends. Cut the asparagus diagonally into one cm wide pieces. Using the back of a knife, spread the sausage meat out of the sausages and form into small dumplings.
Melt 30g butter in a pot. Dust with flour and steam briefly while stirring. Add the stock and 200 ml cream and bring to the boil. Cook the soup for 5 minutes at medium heat, stirring occasionally.
Add the asparagus pieces and dumplings to the soup and continue to cook at medium heat for 10 minutes. Season with salt, pepper, freshly grated nutmeg and a few drops of lemon juice.
Cut the baguette into eight thin slices and fry in the remaining butter until golden brown. Mix the egg yolks in 100 ml cream. Pour egg-cream mixture into the hot soup while stirring (soup must not boil any more).
Sprinkle the soup with cut cress and serve with the baguette.