Bring 6 cups water to a boil in a large pot. Add 2 cups dried pasta and cook about 11 minutes or until tender; drain in a colander.
Toss the hot pasta with 1/2 tablespoon olive oil to prevent sticking and spread it on a tray or leave in the bowl to cool to room temperature, then chill in the refrigerator until fully cold.
In a large mixing bowl combine 1 cup plain Greek yogurt, 1/2 cup mayonnaise, and 2 tablespoons Hidden Valley Ranch dry dip mix; stir until smooth.
Add the chilled pasta, 1/2 rotisserie chicken (about 2 cups cubed), 4–6 chopped green onions, 1 cup shredded Colby Jack cheese, 1 cup peas, 1 teaspoon dried parsley (or 2 tablespoons fresh), 1/4 teaspoon salt, and 1/4–1/2 teaspoon ground black pepper to the dressing; fold gently to combine.
Cover the pasta salad and refrigerate until very cold, at least 30 minutes. Taste and adjust seasoning with more salt, pepper, or mayo if desired before serving.