Cut cherry tomatoes in half lengthwise. Trim cucumber ends, then slice into half-moons about 1/4-inch (6 mm) thick; if using an English cucumber, you can peel every other strip for texture or peel fully if skin is thick.

If using red onion, thinly slice and soak in cold water for 5 minutes to mellow sharpness, then drain and pat dry.

Make dressing

In a small bowl or jar, combine extra-virgin olive oil, fresh lemon juice, red wine vinegar, Dijon mustard, honey, and minced garlic.

Whisk or shake vigorously to emulsify until combined and slightly thickened. Season with salt and freshly ground black pepper and taste; adjust acidity or sweetness by adding a little more lemon juice or honey as desired.

Assemble salad

Place the halved cherry tomatoes and cucumber slices in a large bowl. Add the thinly sliced basil (or parsley) and the drained red onion if using.

Pour the dressing over the vegetables and gently toss with tongs or salad servers until evenly coated. Let the salad sit for 5–10 minutes at room temperature to allow flavors to meld.

Taste and adjust seasoning with additional salt, pepper, or lemon juice if needed. Sprinkle crumbled feta or shaved Parmesan on top if using.

Serve immediately or keep refrigerated for up to 6 hours; if storing, wait to add cheese until just before serving to prevent sogginess.