Spray a large baking dish with cooking spray. Place the broccoli and garlic in the dish, spray with oil, and sprinkle with salt and pepper to taste. Roast the broccoli for about 20 minutes or until tender and just beginning to brown, stirring occasionally. Don't turn off the oven.
While the broccoli is roasting, cook the tortellini according to the package instructions and drain well. (If you don't drain the tortellini well, the bake will be watery, so make sure it's really dry!)
Add the tortellini to the baking dish with the broccoli and toss with the Italian seasoning and marinara sauce. Top with cheese and bake for about 10 minutes, or until the cheese has melted.
To make the Cheese Tortellini Bake in mini-cocottes or ramekins, roast the broccoli on a baking sheet instead of in a baking dish, toss the ingredients together in a bowl, and divide them into the individual mini-cocottes.This makes 2 big servings, or you can get 4 smaller servings out of it and make them a meal by serving a salad on the side.