Bring a large pot of salted water to a boil and cook the pasta according to package directions until al dente, then drain and set aside to cool slightly. While the pasta cooks, dice the cucumber into 1/2-inch pieces, halve or quarter the tomatoes depending on size, finely mince the red onion, chop the fresh parsley, zest and juice the lemon, and mince the garlic. Having all ingredients prepped and ready ensures smooth assembly and allows flavors to develop properly when combined.

In a small bowl, whisk together the olive oil, lemon juice, lemon zest, mustard, dried oregano, minced garlic, salt, and black pepper. The whisking emulsifies the oil and lemon juice slightly while distributing the spices evenly. I find that letting the dressing sit for just a minute allows the garlic to infuse its punch into the oil and lemon base, creating a more cohesive flavor profile.

In a large serving bowl, combine the cooled pasta from Step 1 with the diced cucumber, halved tomatoes, minced red onion, kalamata olives, and fresh parsley. Pour the dressing from Step 2 over the vegetables and pasta, then toss everything together until all ingredients are evenly coated and the flavors begin to meld. The feta cheese should be added just before serving to prevent it from breaking down too much in the acidic dressing.

Top the dressed salad with the feta cheese crumbles and gently toss once more to incorporate without crushing the cheese. Serve immediately for the crispest vegetables and best texture, though the salad can be refrigerated for up to 2 hours if needed.