Wash all vegetables thoroughly under cold water.
Halve the cherry tomatoes and place them in a large bowl.
Dice the cucumber and add it to the bowl with tomatoes.
Dice the bell pepper and add it to the mixture.
Slice the black olives and add them to the bowl.
Finely chop the red onion and include it in the mix.
Add the fresh basil and crumbled feta cheese (if using).
In a small bowl, whisk together olive oil, red wine vinegar, salt, and pepper.
Pour the dressing over the salad and toss gently to combine.
Serve immediately or chill in the refrigerator for 30 minutes for enhanced flavors.