1. Preheat oven to 350 degrees F (180 degrees C). Lightly grease a 3 quart baking dish with cooking spray. Spread about 1/2 cup sauce on the bottom of the dish and arrange half of the ravioli in a single layer over the sauce.

2. Top with cooked sausage, spinach, and sundried tomatoes. Pour 1 1/2 cups of alfredo sauce over the spinach mixture. Sprinkle with half of the mozzarella and Parmesan cheese and top with the remaining ravioli in a single layer.

3. Pour over remaining sauce and top with remaining mozzarella and Parmesan cheeses.

4. Cover and bake for about 1 hour, uncovering during the last 15 minutes, until golden brown around the edges and bubbly. Let stand 10 minutes before serving.

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