For filling, mix together cheeses, egg, salt, and pepper. Fill uncooked manicotti with cheese mixture and place in greased 9x13 pan. May be refrigerated overnight or baked immediately.

To bake, pre-heat oven to 400. (If your manicotti has been refrigerated, be sure to remove it from the refrigerator about an hour before baking time.)

In a saucepan, stir spaghetti sauce and water together; bring to a boil. Pour over manicotti. Cover with foil and bake for 40 minutes.

Remove foil and top manicotti with additional mozarella cheese, if desired; bake for 5-10 minutes more. Serve with additional spaghetti sauce, if desired.

Note: Sometimes if the manicotti has been refrigerated overnight, the shell will crack when the hot sauce is poured over. This is not usually a problem, because the filling helps hold the shell in place, and the mozarella cheese topping covers any visible imperfection.