Peel the fibrous outer layer from the celery stalks with a vegetable peeler. Cut each stalk into three 4” lengths. Put the celery in a large bowl and add the olive oil and a pinch of salt. Toss to coat evenly. Place on the grill, cover, and cook until slightly tender and grill-marked, 2-3 minutes per side.
Transfer the celery to 6 small plates and arrange in a stack on each.
Sprinkle with pine nuts and a little salt. Drizzle with the truffle oil and vinegar. Shave an equal amount of the cheese over each portion. Serve.