- Preheat the oven to 350°F (175°C). 
- In a large bowl, mix together lean ground beef, fresh basil, Italian seasoning, Parmesan cheese, and mozzarella cheese until well combined. 
- Cut the tops off the bell peppers and remove the seeds, leaving space inside for stuffing. 
- Fill each pepper half with the beef mixture, packing it in generously. 
- Arrange the stuffed peppers on a baking sheet, ensuring they have plenty of room. 
- Drizzle olive oil over the top of the stuffed peppers. 
- Bake in the preheated oven for about 45 minutes, or until the peppers are tender and the cheeses have melted and are bubbling. 
- Remove from the oven and let cool slightly before serving. Enjoy your delicious stuffed peppers!