I got this recipe from the cafe at Stihl, Inc. where I am a consultant. The recipe was for 60 servings, so I scaled it down a bit and made my customary changes.
Ingredients:
      1 oz(w) Yellow Onion, diced
      1/8 tsp Garlic, minced
      1 Tbls Butter, Margarine or oil
      37 oz Hot Water
      1 oz(w) Chicken Stock Base (like Minor's)
      6 oz(w) tomato paste
      2 tsp Sugar
      pinch ground white pepper
      11 oz 2% Milk, hot
      1 tsp Fresh Basil, chiffonade
      1 tsp Fresh Parsley, chopped
Directions:
- Saute onions and garlic in butter until tender.  
 
- Add: hot water, chicken base, tomato paste, sugar and white pepper. Mix well and bring to a boil, reduce heat. 
 
- Simmer uncovered for 15 minutes, stirring occasionally. 
 
- Slowly add hot milk while whisking tomato mixture, heat to just simmering again, do not boil. 
 
- Add fresh basil and parsley, remove from direct heat, cover and keep at serving temperature (150-160).