1. Combine purslane, tomatoes, cucumbers, onions, and parsley in a medium bowl. In a smaller bowl, whisk together olive oil, vinegar, and oregano; season with salt and pepper, pour over salad, and mix well. Transfer salad to a serving bowl or individual plates and top with sliced feta, olives, and another pinch of oregano; season with fresh ground pepper and more parsley, if desired.