For the spinach:

1. Sauté the fresh spinach with olive oil in a sauté pan until just cooked through. Add minced garlic, toss well, and sauté for an additional minute. Transfer to a shallow dish and set aside.

For the dumplings:

1. In a medium-size bowl, mix together cooked spinach, ricotta, parmigiano, egg yolks, and flour as needed (the mixture must remain soft but still malleable). Add grated nutmeg, salt, freshly ground pepper, and stir until well combined.
2. Shape into balls in your hands, adding a little bit more flour if the mixture is too soft. Spread 2 to 3 tablespoons of flour in a shallow dish or plate. Roll the dumplings into the flour, until coated completely.
3. Transfer to a tray lined with parchment paper, cover with cling film, and place in the refrigerator for about 2 hours until balls are firm enough to cook (the balls remain soft enough but should be able to keep their shape).
4. Cook the ricotta dumpling in a large volume of boiling water, and cook until the dumplings come on top, about 3-5 minutes.
5. Drain the water through a colander and set aside.

For the tomato sauce:

1. In a large pot, melt onions in olive oil until translucent. Add crushed tomatoes, minced garlic, basil and season with salt and freshly ground black pepper.
2. Cook until the sauce thickens and the water evaporates.
3. Toss the dumplings in the prepared sauce, and serve immediately with additional grated parmigiano, fresh basil and toasted pine nuts.