Cook the tortellini in salted water per the package instructions. Drain well and set aside to cool slightly.
Meanwhile, in a large mixing bowl whisk together the mayonnaise, buttermilk, sour cream, ranch dressing mix, garlic power, onion powder, lemon pepper and dill.
Toss cooked tortellini with dressing. Mix well. Add cheese, bacon, and green onion to the bowl. Mix until evenly coated. (May reserve some of each to garnish, if desired)
Serve immediately warm or place into the fridge to chill for several hours before serving. Garnish as desired.