Prep the peppers: Slice off the tops, remove seeds and membranes, and trim the bottoms slightly if needed so they stand upright. Brush the outsides lightly with 1 tablespoon olive oil and a pinch of salt.

Preheat the air fryer: Set to 360°F (182°C) for 3–5 minutes. Preheating helps the peppers cook evenly and prevents sogginess.

Sauté the aromatics: In a skillet over medium heat, add the remaining 1 tablespoon olive oil. Cook onion for 2–3 minutes until soft, then add garlic for 30 seconds until fragrant.

Cook the protein: Add ground beef or turkey to the skillet. Season with salt, pepper, Italian seasoning, smoked paprika, and red pepper flakes. Cook, breaking it up, until browned and no longer pink, about 5–7 minutes. Drain excess fat if needed.

Add cauliflower rice: Stir in the riced cauliflower and cook 2–3 minutes to soften and reduce moisture. This keeps the filling from getting watery.

Stir in sauce and cheese: Add the sugar-free marinara and Parmesan. Mix well, then fold in 1/2 cup of the mozzarella. Taste and adjust seasoning.

Stuff the peppers: Spoon the mixture into each pepper, pressing down gently to pack it in. Top with the remaining 1/2 cup mozzarella.

Air fry: Arrange peppers upright in the air fryer basket, leaving space between them for airflow. Cook at 360°F (182°C) for 10–14 minutes, until peppers are tender and the cheese is melted and lightly browned.

Finish and serve: Let rest 2–3 minutes. Garnish with chopped parsley or basil. Serve warm.