Preheat oven to 375°F (190°C).
In a large skillet over medium-high heat, cook the Italian sausage until browned and fully cooked, breaking into small crumbles.
Drain excess fat from the skillet, then stir in minced garlic and cook for 60 seconds.
Add marinara sauce, beef broth, and dried oregano to the skillet and bring to a light simmer.
Stir in the uncooked refrigerated tortellini until evenly coated in sauce.
Transfer the mixture to a 9x13 inch baking dish and spread into an even layer.
Sprinkle mozzarella and Parmesan cheese uniformly over the top.
Bake for 20 to 25 minutes until the cheese is melted, slightly golden, and the sauce is bubbling.
Let stand for 5 minutes and garnish with fresh parsley before serving.