- Chop the tomatoes into pieces.
- Slice the cucumbers and the onions in rings. Cut the onion rings in half.
- Cut the green peppers into small pieces.
- Combine tomatoes, cucumbers, onions, peppers, and olives in a deep bowl.
- Add enough olive oil, vinegar or lemon juice, and salt to taste. Toss the ingredients for half a minute.
- Place a feta cheese slice on top and season with a splash of olive oil.
- Top with a sprig of oregano if desired.