In a large bowl, prepare the dressing by combining the mayonnaise, sour cream, milk, Parmesan Ranch Seasoning, chives, dill, parsley, and a pinch of salt and pepper. Mix until smooth and set aside.
Cook the bacon on low heat until crispy, allowing the bacon grease to remain on the griddle. Remove the bacon, chop it into bite-sized pieces, and set aside.
Season the chicken tenders with Blackstone All Purpose Seasoning. Cook the chicken in the reserved bacon grease until fully cooked. Remove from heat, let rest for 5 minutes, then chop into small pieces.
In a large mixing bowl, combine the cooled pasta, chopped chicken, bacon pieces, cheddar cheese cubes, grape tomatoes, purple onion, and green onions. Pour in the dressing and toss everything together until evenly coated.