Prepare the bell peppers: Slice off the tops and remove the seeds and membranes carefully. Stand the peppers upright in a large baking dish.
In a spacious mixing bowl, combine the shredded chicken and buffalo sauce. Add in the softened cream cheese, half of the shredded cheddar cheese, chopped green onions, diced celery, garlic powder, and a sprinkle of salt and pepper. Stir until fully incorporated.
Generously spoon the buffalo chicken mixture into each prepared bell pepper, packing them tightly.
Evenly distribute the remaining cheddar cheese over the tops of each stuffed pepper.
Loosely cover the baking dish with aluminum foil and bake for 30 minutes.
After 30 minutes, carefully remove the foil and continue baking for an additional 10-15 minutes, or until the cheese is melted and bubbly.
Once out of the oven, let the stuffed peppers cool for about 5 minutes before serving. Optionally, sprinkle with blue cheese crumbles.
Notes
Serve on a colorful platter and garnish with extra green onions and buffalo sauce.