Fill a large pot with water, adding a pinch of salt, and bring to a boil. Add the pasta shells and cook until al dente, about 8-10 minutes. Drain and rinse under cold water.

In a mixing bowl, combine mayonnaise, sour cream, and ranch seasoning. Whisk until smooth.

Once pasta is cooled, fold it into the dressing along with bacon, tomatoes, cheese, peas, and green onions.

Cover the bowl and refrigerate for at least 30 minutes to meld flavors.

Before serving, stir gently and add croutons if desired for extra crunch.