A timeless classic, great on its own, or as a side dish
A handful of good quality ingredients is what makes this simple salad so enduring. Go for a decent barrel-aged feta, juicy vine-ripened tomatoes and the best Greek olives you can get your hands on: classic purply-brown to black almond-shaped Kalamata olives, or if you're breaking from tradition, go for a nice plump green variety, like Halkidiki or some Olympian green olives.
I tend to switch depending on what I'm having it with, and who else is eating it - if in doubt, just put your favourites in!
Serves up to eight as a small side dish, or four as a light lunch, from 79 calories per serving for a small side and 159 calories as a light lunch (see below for information re. calories).
Further calorie guidelines if you're counting: Using Olympian/green olives (in brine, drained) and lighter Greek salad cheese, calories as above (79/159). Using Kalamata olives and full fat feta cheese - 105 calories as a small side dish (between eight), 209 calories between four. If you have a large appetite you might want to consider increasing the portion sizes - I have this as a side with a few other dishes. If you're having this as a side dish with another Greek dish containing feta, you could leave the feta cheese out (and reduce the calories accordingly). [Calories in square brackets]
1 cucumber (200g after de-seeding) 
3 large vine-ripened tomatoes (300g) 
1/2 red onion (60g) 
150g feta cheese (or lighter Greek salad cheese if you want to reduce calories - vegetarian feta cheese is available) [420 / 285]
80g olives (e.g. Kalamata, or Olympian) [169 / 102]
1/2 tsp dried oregano (or to taste) 
*1 tbsp olive oil 
*1/2 tbsp red wine vinegar 
Salt and freshly ground black pepper to taste
Chopped fresh parsley to garnish (optional) 
*Further dressing can be added if desired, one part vinegar to two parts oil
Cut the cucumber in half, scrape out the seeds with a small teaspoon, and slice. Cut the tomatoes in half, cut out the core, then place cut side down and cut each half into eight pieces (cut across in half, then cut into four wedges). Cut the onion half through the centre, almost to the root (keep this to hold onto), then slice thinly and dice the feta into small cubes (or cuboids!).
Whisk the oil and vinegar in the bottom of a bowl large enough to hold the salad until emulsified, then whisk in the seasoning. Add the salad vegetables and olives and toss together until thoroughly coated in the dressing. Gently toss in the feta cubes, and serve immediately scattered with the chopped parsley if desired. Will keep in the fridge for a day or two, but the cucumber will lose a little of its crunch.
If you want to bulk this out as a lunch dish, you could serve on top of, or mixed with shredded lettuce (e.g. cos / romaine / little gem) at 16 calories per 100g.
Delicious on its own, or as a side served with grilled meats, or my feta and spinach filo pie.