1. Place the cooked chicken breast on a cutting board and chop into small, even bite-sized pieces. Keeping the pieces uniform helps the dressing coat evenly and creates a better texture.

2. Dice the cucumber and cherry tomatoes into small pieces of similar size. Crumble the feta cheese gently using your fingers so it stays soft and slightly loose. Finely chop the parsley so it distributes evenly throughout the salad.

3. In a large mixing bowl, combine the Greek yogurt, olive oil, lemon juice, dried oregano, salt, and black pepper. Stir continuously for about 1 to 2 minutes until the dressing becomes smooth, creamy, and slightly glossy with no lumps remaining.

4. Add the chopped chicken, cucumber, tomatoes, feta cheese, and parsley into the bowl. Using a spoon or spatula, gently fold everything together for about 1 minute until all ingredients are evenly coated. Avoid overmixing to keep the texture intact.

5. Cover the bowl and place it in the refrigerator for 20 to 30 minutes. This resting time allows the flavors to blend and the dressing to slightly thicken, giving the salad a more cohesive texture.

6. Before serving, stir the salad lightly to redistribute the dressing. If it feels slightly thick, add 1 to 2 teaspoons of olive oil or yogurt and mix gently until creamy again.