Cook the pasta. Bring a large pot of salted water to a boil. Cook the pasta until al dente according to package directions. Drain and rinse under cool water to stop the cooking. Shake off excess water.

Whisk the dressing. In a small bowl or jar, whisk olive oil, lemon juice and zest, red wine vinegar, Dijon, garlic, oregano, salt, pepper, and red pepper flakes. Taste and adjust lemon or salt as needed.

Prep the mix-ins. While the pasta cooks, chop the cucumber, tomatoes, onion, parsley, olives, and roasted red peppers. Rinse and drain the chickpeas. Crumble the feta.

Combine. Add cooled pasta to a large bowl. Flake in the tuna. Add chickpeas, cucumber, tomatoes, onion, olives, roasted peppers, and parsley. If using greens, add them now.

Dress and toss. Pour most of the dressing over the salad and toss gently until everything is coated. Add the feta and toss once more. If it looks dry, add the remaining dressing or a splash of olive oil and lemon.

Rest for flavor. Let the salad sit for 10–15 minutes so the flavors mingle. Taste again and adjust salt, lemon, or pepper.

Serve. Enjoy chilled or at room temperature. Finish with a final squeeze of lemon and a crack of black pepper for brightness.