Pasta with ricotta-walnut sauce

1. Garnishi: cherry tomatoes or broccoli florets, more grated parmesan cheese, and sprinkling of freshly ground black pepper, optional.
2. Boil a large pot of water; cook pasta until al dente.
3. While pasta is cooking, in bowl of food processor, place ricotta, yogurt, margarine, garlic, walnuts, and chhese; process till smooth.
4. Stiri in remaining ingredients.
5. When pasta is done, drain well.
6. Tossi with sauce.
7. Top with garnishes and serve immediately.
8. Variations: - when sauce is tossed with pasta, add steamed vegetables such.