In a large bowl, combine the zucchini, garlic, basil, tomatoes, olive oil, capers, olives, lemon juice, salt. Allow to stand in cool place for 1/2 hour.
Meanwhile, bring 6 quarts water to boil in spaghetti pot and add 2 tablespoons salt. Drop the penne in the pot and cook according to the package instructions until "al dente", about 10 to 12 minutes. Drain the pasta in a colander and add the pasta to the cool vegetables in the mixing bowl. Toss in chili flakes more basil and cracked black pepper. Stir gently to mix well and serve immediately.
Note: this dish is not served hot.