Bring a large pot of salted water to a boil. Add the pasta and cook according to package instructions until al dente. Drain and rinse under cold water to cool down.

In a large bowl, combine the mayonnaise, Greek yogurt, lemon juice, garlic powder, salt, and pepper. Mix well until smooth and creamy.

Add the cooked pasta, cherry tomatoes, and chopped lettuce to the dressing. Toss everything together until the ingredients are well combined and evenly coated with the dressing.

Cover the bowl with plastic wrap and refrigerate for at least 15 minutes to let the flavors meld. Serve chilled or at room temperature.