In a large pot, bring water to a boil and cook the cheese tortellini according to package instructions until al dente. Drain and set aside in a colander.
In a skillet, heat the olive oil over medium heat. Add the ground beef and Italian sausage, cooking until browned and cooked through, about 8-10 minutes. Use a wooden spoon to break the meat into small pieces. Salt and pepper to taste.
Add the pepperoni slices to the skillet and cook for an additional 2-3 minutes until they begin to crisp.
Stir in the marinara sauce, oregano, and basil, allowing it to simmer for 5 minutes.
Add the cooked tortellini to the meat mixture in the skillet, gently stirring to combine and heat through.
Preheat the oven to 375°F (190°C).
Transfer the tortellini and meat mixture to a greased baking dish. Sprinkle the shredded mozzarella and grated Parmesan cheese evenly over the top.
Bake in the preheated oven for 15-20 minutes, until the cheese is melted and bubbly.
Remove from the oven and let cool for a few minutes before serving.