I use this very simple recipe from the The American vegetarian cookbook: from the fit for life kitchen. You can use this recipe instead of the ricotta in this way or you can mix it through your (home made) tomato sauce.

Blend 3/4 of the tofu with the nutmeg and salt. Add some water to smooth. Mash the rest of the tofu through with a fork.
Posted to fatfree digest by "Boxel" <boxel@sr.net> on May 21, 1998