Haven't tried this yet, but when I first found out I was pregnant and saw this I thought, this would be amazing!
1 Large English hot house cucumber or 3 small cucumbers, peeled, coarsely chopped (about 2-1/2 cups)
2 avocados, peeled, coarsely chopped (about 2 cups)
1 med sweet onion, peeled, coarsely chopped (about 1-1/2 cups)
1-1/2 cups water
1 cup loosely packed cilantro leaves
1/3 cup fresh lime juice
1/2 to 1 whole small jalapeno, seeded, chopped
1/2 tsp ground cumin
1/2 tsp salt
Additional cilantro leaves for garnish
Combine first 9 ingredients in a blender, blend until pureed. Thin soup with additional water, if desired. Season to taste with additional salt, if desired. Cover and refrigerate until cold, at least 3 hours and up to 1 day. Ladle scant 1 cup soup into each 5 shallow bowls or teacups. Top each serving with a dollop of yogurt and float cilantro leaves atop soup as garnish. Serve chilled.
from Essentially Lilly's Guide to Colorful Entertaining