Bring a large pot of salted water to a boil. Add 3 cups of pasta and cook until al dente, around 8–10 minutes. Drain and rinse under cold water.

Season 2 grilled chicken breasts with olive oil, salt, pepper, and oregano. Grill over medium heat for 6–8 minutes per side until cooked through. Let rest before slicing.

In a small bowl, whisk together ¼ cup olive oil, 2 tablespoons lemon juice, 1 teaspoon Dijon mustard, 1 teaspoon honey, and 1 minced garlic clove. Add oregano, salt, and pepper to taste.

In a large mixing bowl, combine the cooled pasta, chicken, 1 cup tomatoes, 1 diced cucumber, ½ sliced red onion, ½ cup olives, and ½ cup feta. Toss gently.

Drizzle the dressing over the salad, toss to coat, and let chill in the refrigerator for at least 30 minutes before serving.