Preheat the oven to 375°F (190°C). As the oven heats, prepare the bell peppers by cutting off the tops, removing the seeds and ribs, and brushing the exterior with 1 tsp olive oil for enhanced flavor.
In a large skillet over medium heat, add 1 tsp olive oil. Once heated, add 1 small chopped onion and 2 minced garlic cloves. Sauté for about 2-3 minutes until translucent and fragrant.
Add the 1 lb ground Beef to the skillet. Season with 1 tsp paprika, 1/2 tsp black pepper, and salt to taste. Cook thoroughly until the Beef is browned and cooked through, about 5-7 minutes. If you opt to use 1 cup cooked rice or quinoa, stir it in once the Beef is cooked, mixing well to combine.
For the gorgonzola sauce, melt 1 tbsp butter in a separate saucepan over medium heat. Slowly stir in 1 cup heavy cream until it begins to simmer gently. Add 1/2 cup gorgonzola cheese, stirring until the cheese melts and the sauce is smooth. Season the sauce with 1/4 tsp nutmeg and 1/4 tsp black pepper, mixing well.
Combine half of the gorgonzola sauce with the Beef filling to enhance the flavors. Stuff the prepared bell peppers generously with the mixture and place them upright in a baking dish.
Drizzle the remaining gorgonzola sauce over the stuffed peppers and top with 1/2 cup shredded mozzarella or cheddar cheese for an indulgent finishing touch.
Bake the stuffed peppers covered with foil for 20 minutes. After that, remove the foil and bake uncovered for an additional 10 minutes, or until the cheese is bubbly and golden.