1largeEnglish cucumberquartered lengthwise and cut crosswise into ½-inch pieces (about 2 ¼ cups)
1smallred onionquartered and thinly sliced (about ½ cup)
¾teaspoonkosher saltplus more as needed
4mediumtomatoescut into 1-inch pieces (about 3 cups)
3tablespoonsfresh parsley, dill, or mint leavesfinely chopped
2tablespoonsred wine or white wine vinegar
1tablespoonextra-virgin olive oil
½teaspoongranulated sugaroptional
freshly ground black pepper
Instructions
Place chopped cucumber and sliced red onion in a medium bowl. Sprinkle with kosher salt and toss to combine. Let sit for 20 minutes.
Pour off any liquid from the cucumber mixture. Add chopped tomatoes, chopped fresh herb leaves, red wine vinegar, olive oil, and granulated sugar if desired. Toss to combine. Taste and season with more kosher salt and black pepper as needed.