Classic Spinach Lasagna

Directions

1. 1
   Put the dried mushrooms in a bowl and pour 1 cup boiling water over them.
2. 2
   Let them sit for 30 minutes, then drain, reserving the water.
3. 3
   Rinse the mushroom pieces thoroughly, chop them fine, and rinse again to remove all traces of grit.
4. 4
   Line a sieve with a dampened paper towel and strain the mushroom-soaking liquid into a small bowl.
5. 5
   Heat the olive oil in a large non-reactive skillet.
6. 6
   Add the pancetta and onion and saute over low heat 5 minutes.
7. 7
   Raise heat to medium, crumble in the ground beef, and add 1/4 teaspoon of salt and several grindings of fresh pepper.
8. 8
   Saute 5 more minutes, stirring to break up the meat.
9. 9
   Add the chopped chicken livers and the chopped porcini.
10. 10
    In a measuring cup, combine 1/2 cup of the mushroom-soaking liquid and 1/2 cup hot water.
11. 11
    Dissolve the tomato paste in this liquid and add it to the skillet.
12. 12
    Bring to a simmer, cover the pan and cook 1 hour, stirring occasionally and regulating the heat to maintain a gentle simmer.