In a medium bowl, combine the cucumber, scallion, tomato, and Feta.
Scatter the parsley leaves on top, sprinkle on the red pepper flakes, and drizzle with olive oil.
Toss well to combine. Serve at room temperature or chilled.
Notes
Store the Tomato Cucumber Feta Salad in an airtight container in the refrigerator for up to 2 days. It's best enjoyed fresh, as the cucumbers and tomatoes may become soggy over time.