The flavors of lime, cilantro and avocado combine in this creamy gazpacho. The cucumber contributes a light crunch.
Put 2 avocados, vegetable stock, 1/2 cup water, 1/4 cup scallions, lime juice, cumin and hot pepper sauce in food processor or blender, and purée until smooth. Transfer soup to non-metallic container, cover and refrigerate until chilled, 1 to 2 hours.
To serve, chop remaining avocado, and stir it, as well as remaining scallions, tomatoes, cucumber and cilantro, into soup. Ladle into bowls, and garnish with dollop of sour cream, if using.