1. Preheat oven: Preheat your oven to 375°F (190°C). Lightly grease a baking dish large enough to hold the peppers snugly (about 9×13 inches or similar).
2. Prepare the peppers: Trim the tops of the peppers and remove seeds and membranes. If needed, level the bottoms slightly so they stand upright (careful not to make a hole). Place peppers upright in the prepared baking dish.
3. Cook aromatics: Heat olive oil in a skillet over medium heat. Add the chopped onion and cook 3–4 minutes until softened. Add the garlic and cook 30 seconds until fragrant.
4. Brown the meat: Add the ground meat to the skillet, breaking it up with a spoon. Cook until browned and no longer pink, about 5–7 minutes. Drain excess fat if there’s a lot, leaving a little for flavor.
5. Make the filling: Stir in the cooked rice, drained diced tomatoes, Italian seasoning, Worcestershire sauce (if using), paprika, salt, pepper, and half of the shredded cheese. Add any optional mix-ins (beans, corn, mushrooms). Cook 2–3 minutes to combine and warm through. Taste and adjust seasoning.
6. Fill the peppers: Spoon the filling into each pepper, packing gently and mounding slightly at the top. If using, pour the marinara/tomato sauce into the bottom of the baking dish (about 1/2 cup–1 cup) to keep peppers moist and add flavor; you can also spoon a little sauce over each pepper.
7. Cover and bake: Cover the dish tightly with foil and bake for 30 minutes.
8. Add cheese and finish baking: Remove foil, sprinkle the remaining cheese over the tops of the peppers, and bake uncovered another 10–15 minutes, until the cheese is melted and the peppers are tender when pierced with a fork. If you like a bit of browning, broil 1–2 minutes—watch carefully.
9. Rest and garnish: Let the peppers rest 5 minutes out of the oven. Garnish with chopped parsley or basil before serving.
10. Serve: Serve the stuffed peppers with extra tomato sauce from the dish spooned over the top, and a side salad or crusty bread to soak up any juices. Leftovers keep 3–4 days refrigerated; reheat covered in the oven or microwave.

Tips

• For a lighter version, substitute ground turkey and use brown rice or cauliflower rice.
• To save time, use precooked rice (leftovers) or a cup of frozen mixed vegetables.
• Make ahead: assemble peppers, cover, and refrigerate up to 24 hours before baking—add a few extra minutes to the bake time if cold from the fridge.
• For extra flavor, stir 1/4 cup grated Parmesan into the filling or sprinkle on top with the cheese.

Simple, cozy, and flexible — stuffed peppers are dinner that feels like a warm hug.