Wash and thoroughly dry romaine hearts using a salad spinner or kitchen towels. Chop into bite-sized pieces and place in a large mixing bowl.
Drizzle extra virgin olive oil over the chopped romaine. Toss gently but thoroughly to coat every leaf lightly.
Add finely grated Parmigiano-Reggiano to the bowl. Toss again until cheese distributes evenly throughout the salad.
Squeeze fresh lemon juice over the top. Start with 2 lemons, taste, and add more if desired for extra tang.
Toss one final time to combine all ingredients. Season with salt and freshly cracked black pepper to taste.
Let salad rest for 2-3 minutes to allow flavors to meld. Serve immediately, garnished with chopped chives if desired.