Prep the oven and pan. Preheat your oven to 400°F (200°C). Line a baking sheet or 9x13-inch baking dish with parchment or lightly grease it.

Halve and prep the peppers. Slice peppers in half lengthwise and remove seeds and membranes. Rub the cut sides with a little oil and a pinch of salt. Arrange them cut side up on the pan.

Soften the cream cheese. In a large bowl, microwave the cream cheese for 20–30 seconds until it’s easy to stir. This helps everything mix smoothly.

Make the filling. Add shredded chicken, buffalo sauce, garlic powder, onion powder, half the mozzarella, the cheddar, a tablespoon of ranch (optional), and a pinch of salt and pepper. Fold in green onions and diced celery if using. Mix until creamy and well combined.

Pre-bake the peppers. Bake the pepper halves for 10 minutes to start softening them. This helps prevent crunchy edges and speeds up the final bake.

Stuff generously. Spoon the buffalo chicken mixture into each pepper half, packing it slightly. Top with the remaining mozzarella and a sprinkle of blue cheese if you like.

Bake until bubbly. Return to the oven for 15–18 minutes, or until the cheese is melted and the peppers are tender. For browned tops, broil for 1–2 minutes at the end, watching closely.

Finish and serve. Let them rest for 5 minutes. Drizzle with ranch or blue cheese dressing and add extra green onions for brightness. Serve hot.