In a medium bowl mix together ricotta and eggs until blended. Stir in spinach, mozzarella cheese, 1/4 cup of the Parmesan cheese, sugar, salt and pepper. Stuff mixture into uncooked cannelloni shells.
Spread 1/2 cup spaghetti sauce in the bottom of a medium baking dish. Arrange stuffed pasta shells in a single layer over the sauce. Pour the remainder of the sauce over the shells, cover dish and chill in the refrigerator for 8 hours, or overnight.
Preheat oven to 200 degrees C. Bake covered for 40 minutes. Sprinkle with remaining Parmesan cheese and bake for another 15 minutes.
Really liked this recipe. I liked the fact that it can be prepared ahead of time. A piping bag is a required tool for this recipe but getting it into the shell was the only time consuming bit. My only tip would be to add a spicy sauce as mine was not quite spicy enough using passatta. 2 of the 3 children loved it, 1 liked it. - 27 Jun 2012