Soak the porcini mushrooms in 1/2 cup of warm water for about 30
minutes. Drain, reserving the liquid. Rinse, dry, and chop the
porcini mushrooms. Strain the soaking liquid through washed
cheesecloth, paper towels, or a coffee filter. Set aside.
Melt the butter and 1 tb of olive oil in a large pot over low heat.
Add the onion and garlic. Cook, stirring frequently, until the
onion is wilted but not browned, about 5 minutes.
Add the porcini mushrooms and cook for 8 minutes. Increase the heat
to medium and add the fresh mushrooms. Cook until the juices run,
about 10 minutes. Add the reserved porcini soaking liquid and
continue to cook until reduced by half, about 5 minutes. Add the
tomatoes, salt, pepper, marjoram, and thyme; cook for 5 minutes.
Add the broth and simmer for 15 minutes.
While the soup is cooking, toast the bread in a 400 F oven until
lightly browned on both sides. Remove and brush one side with the
remaining olive oil. Use more oil if necessary.
In a small bowl, beat the egg yolks with the Parmesan cheese, the
pecorino romano cheese, and 3 tb of chopped parsley. Gradually
whisk 1 cup of the hot soup into the egg yolks to warm them.
Reverse and slowly whisk the egg yolk mixture into the soup. Cook,
stirring constantly, over medium-low heat until the soup thickens.
(Do not boil or the soup will curdle.)
Place a piece of toast in each of 8 bowls. Ladle in the hot soup
and sprinkle with additonal grated Parmesan cheese and chopped
parsley.
