Prepare a large bowl of ice water and set aside. Bring a large pot of salted water to a rolling boil.
Add trimmed green beans to the boiling water and blanch for 3-4 minutes until bright green and crisp-tender.
Immediately transfer beans to the ice water bath to stop cooking. Let sit for 1-2 minutes.
Drain the beans thoroughly and pat dry with paper towels or a clean kitchen towel.
In a large mixing bowl, combine the cooled green beans, thinly sliced red onion, and halved cherry tomatoes.
In a small bowl, whisk together olive oil, lemon juice, salt, and pepper. Add optional garlic, Dijon, or honey if using.
Pour dressing over vegetables and toss gently to coat everything evenly.
Sprinkle crumbled feta cheese over the salad. Add optional toasted almonds or herbs if using.
Gently toss once more, being careful not to break the beans or crush the tomatoes.
Taste and adjust seasonings as needed. For best flavor, refrigerate for at least 30 minutes before serving.
