I took a recipe from Penzeys Spices and adapted it for low carb.
1 bundle of Asparagus
1 small onion
3 tbs unsalted butter
1 cup of chicken stock
1 cup of water
1 cup of cream
1 Tbsp Arrowroot (here you can use another low carb thickener -
I had carbs to spare today)

1/2 tsp of white pepper
1/2 tsp garlic
1/2 tsp salt (if necissary)
1/2 tsp Fine Herbes (mixture of chervil, parsley, chives and tarragon)

Cook Asparagus and onion in the butter for 8-10 minutes
Add chicken stock and water cook for 8-10 minutes more
Add cream with Arrowroot, bring to a low boil.
Let it cool slightly and put into a blender and puree till its at the consistancy you like. I like little bits of the veggies, myself.

For the whole thing its:
Total Calories: 1055
Fat: 99
Sat: 67
Poly: 10
Mono: 21
Carbs: 16
Fiber: 0
Protein: 9
Alcohol: 0

This makes 3 cups of soup. so for 6 people it would be about 176 calories, 2.6 carbs for a half cup of soup.