Begin by taking the tips off of the asparagus. Cut just below the "woody" part or the top before the stem. Chop the rest of the asparagus into 1/2 pieces. Melt the butter in a fry pan. Add the onion and asparagus stirring to coat. Add in the chicken broth, potato, and spices. Bring to a boil and cook uncovered 10-12 minutes. While your mixture is cooking in the fry pan, combine the asparagus tips and the water. Microwave on high for 1 minute. Place the soup from the fry pan into a blender and puree until smooth. You can also use a hand blender but put the soup into a tureen or large bowl first. Stir in the heavy cream until well blended. Garnish with the steamed asparagus tips. Spoon into bowls and serve warm.