01 - Preheat the oven to 375°F. Lightly grease a baking dish large enough to fit all peppers upright.
02 - Slice the tops off the bell peppers and remove the seeds and membranes. Arrange peppers in the prepared baking dish.
03 - In a large bowl, combine shredded chicken, cottage cheese, buffalo sauce, ranch dressing (or Greek yogurt), chopped celery, green onions, garlic powder, onion powder, salt, and pepper. Mix well.
04 - Spoon the chicken mixture evenly into each bell pepper, filling them generously.
05 - Sprinkle mozzarella cheese and blue cheese (if using) evenly over the tops of each stuffed pepper.
06 - Cover the dish loosely with foil and bake for 25 minutes.
07 - Remove foil and bake an additional 10 minutes, or until the cheese is golden and the peppers are tender.
08 - Let cool for 5 minutes before serving. Garnish with extra green onions if desired.