1. In a large pot, bring potatoes to a boil in salted water over high. Reduce to a simmer and cook until tender when pierced with a knife, 15 to 20 minutes. Drain and let cool completely. Cut potatoes into 1 1/2-inch pieces.

2. In a large bowl, combine olive oil, garlic, lemon juice, and Parmesan. Add potatoes and toss to combine. Season with salt and pepper. Add romaine hearts just before serving. To store, cover and refrigerate up to 1 day.