2 ½ pounds cucumbers (6 to 8 large or 16 to 20 Kirbys), peeled
3 scallions, trimmed
2 teaspoons white-wine vinegar, plus more as needed
½ teaspoon sea salt, plus more as needed
¼ teaspoon freshly ground black pepper, plus more as needed
1 medium tomato
1 tablespoon shredded fresh basil
1 tablespoon extra-virgin olive oil
Cut the cucumbers in half lengthwise. Use a small spoon to scoop out/discard seeds.
Cut enough cucumbers into ½-inch dice to yield 1/2 cup. Cover and refrigerate it for salsa.
Cut remaining cucumbers into 1-inch chunks. Chop 2 of the scallions.
In bowl of a food processor or blender jar, combine larger cucumber chunks and chopped scallions with the vinegar, 1/2 teaspoon salt, ¼ teaspoon pepper and 1 ½ cups water; puree until smooth. Taste and add vinegar, salt and/or pepper as needed. Pour into an airtight container and refrigerate until cold, for about 2 hours. May refrigerate for up to 5 days or froze for up to 6 months.
Just before serving, cut the tomato in half through stem end. Discard core and squeeze halves to discard some gel/seeds and juice. Cut remaining tomato into ½-inch dice; transfer to a small bowl.
Thinly slice remaining scallion and add to bowl, along with reserved, diced cucumber and the basil. Toss with the oil and season lightly with salt and pepper.
Taste soup again for seasoning (it will be more muted when cold) and add vinegar, salt or pepper as needed. Divide among chilled bowls, top each portion with some salsa and serve.
Makes 4 servings (makes about 4 cups).
— Recipe adapted by The Washington Post from "The Italian Vegetable Cookbook," by Michele Scicolone (Houghton Mifflin Harcourt, 2014).