Put a large pot of water on to boil.
While you wait for the water to boil, wash the greens and remove any large stems.
When the water boils, cook the pasta.
Then, sauté the garlic over medium heat in olive oil for just a minute. Do not let it turn brown. Turn up the heat to high and add the wet greens and stir well with tongs as you add them to coat them in hot oil. (This helps them stay bright green.) Saute, stirring often until they are just wilted. Turn up the heat to high and season with salt and pepper.
Puree the greens with the nutmeg and ricotta in a food processor. Add more salt and pepper to taste. As soon as you drain the cooked pasta, mix it with the sauce. Serve with optional toppings you like.