1. Preheat your oven to 375°F (190°C). Line a baking dish with parchment paper or lightly grease it with 1 tablespoon of olive oil.
2. Prepare the bell peppers by cutting off the tops and carefully removing the seeds and membranes. Set aside.
3. Heat the remaining tablespoon of olive oil in a skillet over medium heat. Add the chopped onion and sauté for 3-4 minutes until soft and translucent.
4. Add the minced garlic and cook for another minute until fragrant. Stir in the cooked Italian sausage or diced pepperoni, mixing well to combine.
5. In a large bowl, combine the cooked rice (or quinoa), the sausage mixture, marinara sauce, Italian seasoning, red pepper flakes (if using), salt, and pepper. Stir in half of the shredded mozzarella cheese and all of the Parmesan cheese.
6. Stuff each bell pepper generously with the filling, pressing down slightly to pack the mixture in.
7. Place the stuffed peppers upright in the baking dish. Sprinkle the remaining mozzarella cheese on top of each pepper.
8. Cover the baking dish loosely with aluminum foil and bake for 30 minutes. Remove the foil and bake for an additional 10-15 minutes, until the cheese is bubbly and golden.
9. Remove from the oven and let the peppers rest for 5 minutes. Drizzle with a little extra marinara sauce and garnish with fresh basil leaves if desired.

One thing Mama Lou always reminded me was to keep an eye on the cheese’s color—she said, “Sofia, when it’s golden and bubbling, you know it’s ready to make memories.” I still say those words every time I pull a pan of stuffed peppers from the oven.