Cucumber-Dill Soup with Scallions

Thinly slice half of the cucumbers crosswise. Thinly slice half of the scallions crosswise. Set aside. Coarsely chop the remaining cucumbers and scallions and transfer to a large bowl. Add the dill, garlic, lemon juice, buttermilk, and yogurt, and give a good but gentle stir. Season with salt and pepper and puree in a blender until liquefied. (NOTE: You can use a food processor, but a blender will give a smoother, more pleasing result.) Transfer the soup to a large bowl and add the reserved sliced cucumbers and scallions. Adjust seasoning with salt, pepper, and Tabasco to taste. Chill for at least 2 hours in the refrigerator.