In a medium bowl, whisk together Greek yogurt and mayonnaise until smooth. Gradually add red wine vinegar and lemon juice, whisking until emulsified. Pour in olive oil, mixing until fully blended. Stir in herbs, honey, and Parmesan, adjusting seasonings to taste.

Chop the romaine lettuce and place it in a large salad bowl. Halve the cherry tomatoes, slice the cucumber and red onion, and add them to the bowl with sliced pepperoncini.

Add pitted kalamata olives and crumbled feta cheese to the bowl with the romaine. Pour the homemade dressing over the salad and gently toss using salad tongs.

Just before serving, add croutons and toss lightly. Sprinkle with freshly ground black pepper and serve immediately.