In a large stock pot, bring 8 cups of vegetable broth to a boil.
Clean, de-stem, and chop two bunches of spinach. Peel 2 cloves garlic. Drain and rinse the cannellini beans.
Add 2 tablespoons olive oil to a large skillet, place the whole garlic cloves in the pan, and heat for several minutes to infuse the oil. When the garlic has browned, remove and discard it. Add the spinach to the skillet, stir to combine it with the oil, and heat, covered, for 3 minutes.
When the broth has come to a boil, add the wilted spinach and cook for two minutes at a steady simmer.
In a liquid measuring cup or small bowl, beat 3 eggs with a fork. Grate 1/2 cup of Parmesan or Pecorino cheese and add to the beaten eggs. Temper the eggs by drizzling a small amount of the hot broth into the eggs while beating the eggs.
With a spoon, rapidly mix the soup broth to create a “whirlpool” and slowly pour the egg mixture into the soup (don’t stop stirring). The eggs should immediately form into “rags”. Make sure that that broth is at a steady simmer before you add the eggs; if the broth is not hot enough, the eggs may incorporate into the broth instead of forming rags.
Add the cannellini beans. Season with about 1 teaspoon of kosher salt (to taste) and lots of fresh ground pepper. Serve immediately.