Preheat the oven to 375°F (190°C).
Slice the bell peppers into 1-inch rings and remove the seeds.
Lightly brush the rings with olive oil and place them on a parchment-lined baking sheet.
Heat a skillet over medium heat and sauté the onions and garlic until fragrant.
Add the ground beef (or meat alternative) and cook until browned. Drain excess fat.
Stir in cooked rice, diced tomatoes, Italian seasoning, smoked paprika, salt, and black pepper.
Cook for another 2-3 minutes to let the flavors combine.
Spoon the filling mixture into each bell pepper ring, pressing down lightly to keep it in place.
Top each ring with shredded cheese for a melty, golden topping.
Place the baking sheet in the preheated oven and bake for 15-20 minutes, or until the peppers are tender and the cheese is melted and bubbly.
Remove from the oven and let cool for a few minutes before serving.
Garnish with fresh parsley or basil and add a dollop of sour cream or Greek yogurt if desired.