Carefully slice the tops off each bell pepper and remove the seeds and membranes. Rinse the insides under cool water if needed. Set the prepared peppers aside in a baking dish, cut side up.
In a large skillet, warm the olive oil over medium heat. Once the oil shimmers, add the chopped spinach. Sauté for about 2-3 minutes until the spinach is wilted.
In a mixing bowl, combine the sautéed spinach with the ricotta cheese, half of the shredded mozzarella, the grated Parmesan, garlic powder, onion powder, and a generous pinch of salt and pepper. If you like a bit of heat, add the red pepper flakes. Stir well until all ingredients are evenly incorporated.
Take a generous spoonful of the ricotta and spinach mixture and stuff it into the bell peppers, pressing down gently. Continue until all the filling is used.
Sprinkle the remaining mozzarella cheese evenly over the top of each stuffed pepper.
Cover the baking dish tightly with aluminum foil and place it in the preheated oven. Bake for 25 minutes. After this, carefully remove the foil and continue to bake for an additional 10-15 minutes, until the cheese is melted and bubbly.
Once cooked, take the stuffed peppers out of the oven and let them cool for a few minutes before serving. Garnish each pepper with torn basil leaves just before plating.
Notes
Serve on a beautiful platter, drizzled with olive oil and a sprinkle of extra Parmesan.