Bring a large pot of salted water to a boil and cook the bowtie pasta according to package instructions until al dente.
Drain the pasta and rinse it under cold water until completely cooled to stop the cooking process and prevent sticking.
While the pasta cooks, fry the bacon in a skillet over medium heat until crispy, then transfer it to a paper towel-lined plate and crumble once cooled.
Transfer the cooled pasta to a large mixing bowl.
Add the crumbled bacon, chopped romaine lettuce, cherry tomatoes, green onions, and red onion to the bowl with the pasta.
In a separate bowl, whisk together mayonnaise, sour cream, ranch seasoning, lemon juice, garlic powder, salt, and black pepper until smooth and creamy.
Pour the dressing over the pasta mixture and toss gently until everything is evenly coated.
Cover and refrigerate the salad for at least 20–30 minutes before serving for the best flavor.
Toss lightly again before serving and top with extra bacon pieces and green onions if desired.