Bring a pot of salted water to a boil. Add the cauliflower florets and blanch for about 2–3 minutes until slightly tender but still crisp.
Drain the cauliflower and immediately rinse with cold water to stop the cooking. Pat dry.
In a large bowl, whisk together olive oil, lemon juice, red wine vinegar, garlic, oregano, salt, and pepper.
Add the cauliflower to the bowl and toss well so the florets absorb the marinade.
Add cherry tomatoes, cucumber, red onion, olives, parsley, and mint. Toss gently to combine.
Cover and refrigerate for at least 30 minutes so the flavors can develop.
Before serving, sprinkle with crumbled feta cheese if desired and give the salad a gentle toss.
