1. Peel the potatoes and cut them into 1/4-inch-thick slices. Combine the potatoes and chicken broth in a large saucepan or deep skillet. Simmer, partially covered, until the potatoes are just tender, 5 to 8 minutes.
2. Drain the potatoes, reserving the broth. Transfer the potatoes to a wide, shallow bowl. Return the broth to the saucepan or skillet or boil over high heat until reduced to 1/2 cup, 10 to 15 minutes. Pour the broth over the potatoes and mix gently until it is absorbed.
3. In a medium skillet, preferably nonstick, heat the butter over medium heat until bubbly. Add the prosciutto and sauté, stirring, until crisp, about 5 to 8 minutes.
4. Gently mix the prosciutto and butter into the potatoes.
5. Fold in the celery, onion, and chives.
6. In a small bowl whisk the truffle oil and lemon juice until blended. Drizzle this over the potatoes and toss to coat.
7. Taste for seasoning and add salt and pepper as needed. Serve warm or at room temperature.