Preheat oven to 375°F (190°C). Wash bell peppers thoroughly. Carefully slice each bell pepper in half lengthwise, from stem to base. Remove and discard the seeds and white membranes. Place the bell pepper halves cut-side up in a large baking dish.

Heat olive oil in a large skillet over medium-high heat. Add the ground chicken and cook, breaking it up with a spoon, until browned and cooked through, about 5-7 minutes. Drain any excess fat.

Add the finely diced yellow onion to the skillet with the cooked ground chicken. Sauté for 3-4 minutes until softened. Stir in the minced garlic, chili powder, ground cumin, and smoked paprika. Cook for another minute until fragrant. Season with salt and black pepper to taste.

Remove the skillet from heat. Add the softened cream cheese, 1/2 cup shredded cheddar cheese, and 1/4 cup chopped green onions to the chicken mixture. Stir well until the cream cheese is fully melted and everything is combined into a creamy, cohesive filling.

Spoon the cream cheese chicken filling generously into each bell pepper half. Don't be shy – pile it high!

Place the stuffed bell peppers in the preheated oven. Bake for 20 minutes.

After 20 minutes, sprinkle additional shredded cheddar cheese over the top of each stuffed pepper. Return to the oven and bake for another 5-10 minutes, or until the peppers are tender, the filling is hot and bubbly, and the cheese topping is melted and lightly golden.

Carefully remove the baking dish from the oven. Let the stuffed peppers cool for a few minutes before serving. Garnish with extra chopped green onions or fresh cilantro, if desired. Serve hot with salsa or sour cream on the side.