Preheat the oven to 375°F (190°C). Add the olive oil to a baking dish and spread it to coat evenly.
Cook the tortellini in boiling water until they float to the top, about 1 to 2 minutes. Drain.
Toss the tortellini with the pasta sauce and stir to combine well.
Sprinkle with mozzarella cheese and Parmesan cheese, followed by the chopped parsley.
Bake uncovered for 20 to 25 minutes, or until the cheeses are melted and the top and edges are golden brown. Let stand for 5 minutes before serving.