How to Make It
In a large pot of boiling salted water, cook the pasta until al dente. Drain well and toss with 1 tablespoon of the extra-virgin olive oil.
In a saucepan of boiling salted water, blanch the water chestnuts for 1 minute. Drain and slice 1/4 inch thick.
In a large bowl, mix the remaining 1/3 cup of olive oil with the scallions, lemon juice and garlic. Season with salt and pepper. Add the pasta, frisée, tuna and the water chestnuts or apple; toss well and serve.