Soften the dried mushrooms by submerging them in lukewarm water for 20 minutes. When the mushrooms are soft, put half the oil in a pan over medium heat, gently squeeze the liquid out of the mushrooms and add them to the pan with the salt, pepper and 3 tablespoons of the water in which they soaked.
Cook over low heat for 10 minutes. When done, puree in a vegetable mill or food processor with some of the cooking liquid (about half) and set aside. Heat the rest of the oil in another pan and lightly brown the peeled garlic.
As soon as the garlic has browned, remove it from the pan and add the mushrooms with the cooking liquid. Stir for one minute over high heat. Remove from heat, add the rinsed, skinned and finely chopped anchovies. Salt and pepper to taste and keep warm.
Meanwhile, cook the bucatini in a large pot of lightly salted boiling water for the time indicated on the package. Drain the pasta and dress with the sauce prepared as above, adding the chopped parsley at the last minute and mixing well.
Brown the coarsely chopped pieces of bread in a pan with a tablespoon of extra virgin olive oil for a few minutes, pour the bucatini into a baking dish, sprinkle with the bread and bake in a preheated 400° oven or under the broiler for 3-4 minutes to top-brown the pasta. Serve immediately.