Using a sharp knife, cut the tomatoes into bite-sized pieces. A medium tomato could be cut into 8 pieces.
Slice the cucumber into half moons.
Thinly slice a white salad onion or a red onion.
Remove the stem, seeds, and white pith from a green pepper and slice it into strips.
Once all the vegetables are in a serving bowl, add the olives, and optional capers. Drizzle with olive oil (don't be stingy), and a light splash of red wine vinegar, then very gently give the salad a quick toss.
Add a generous slab of feta cheese on top, then drizzle the slab with more olive oil, a sprinkle of dried oregano and a pinch of fine sea salt.