In a medium pot over medium high heat, saute diced onions and garlic in olive oil for 1 minute. Add remaining ingredients except for cream. Bring to boil, reduce heat to low, and simmer for 5 minutes.
Remove soup from heat. Working in batches, puree soup in blender. NOTE: When blending hot liquids, only fill blender bowl halfway and place kitchen towel over lid. Always start with lower blender settings before puree setting.
Adjust seasoning with salt and pepper. Return puree to saucepan, add cream and heat through. Serve hot, garnished with chopped fresh basil.