Preheat your oven to 375°F (190°C).

Cut the green bell peppers in half lengthwise and remove the seeds. Blanch the pepper halves in boiling water for 1-2 minutes. Drain and set aside to cool.

In a skillet, heat oil over medium heat. Cook ground beef and onions until browned and translucent, about 5-7 minutes. Drain excess fat.

Stir in the pizza sauce, season with salt and pepper, and let simmer for 3 minutes.

Reduce heat and stir in cream cheese until smooth. Fold in shredded cheddar cheese.

Stuff the halved peppers with the filling and top with shredded mozzarella. Place in a baking dish.

Cover with foil and bake for 25-30 minutes, removing foil for the last few minutes to brown the cheese.

Let rest for 5 minutes before serving. Garnish with olives or pepperoni if desired.