Slice the tops off the bell peppers and remove the seeds and membranes. Lightly brush the exterior of the peppers with olive oil and place them upright in a baking dish.
In a large skillet over medium heat, add the olive oil. Sauté the chopped onion and minced garlic until the onion is translucent.
Add the ground beef (or turkey) to the skillet and cook until browned, breaking it apart as it cooks. Drain any excess fat.
Stir in the cauliflower rice, Italian seasoning, smoked paprika, and half of the shredded cheddar cheese. Season with salt and pepper to taste. Cook for an additional 2-3 minutes until everything is heated through.
Remove the skillet from the heat. Carefully spoon the stuffing mixture into each bell pepper until they are packed full.
Top each stuffed pepper with the remaining cheddar cheese.
Cover the baking dish with foil and bake for 25 minutes. Then, remove the foil and bake for an additional 10-15 minutes, or until the peppers are tender and the cheese is bubbly and golden.
Once cooked, let them cool for a few minutes before serving. Garnish with freshly chopped parsley.