Reconstitute the mushrooms in boiling water for 20 minutes until tender, drain and coarsely chop.
Puree the mushrooms, pancetta, onion, celery stalks, carrots, garlic, together in a blender.
In a heavy-bottomed pot add olive oil, bay leaves, herbs and cook gently until fragrant, then add vegetable puree and continue to cook for a further 5 to 10 minutes.
Raise the heat a bit and add the ground pork and beef; brown until the meat is no longer pink, breaking up the clumps with a wooden spoon. Add the milk and simmer until the liquid is evaporated, about 10 minutes. Carefully pour in the tomatoes, and wine and season with salt and pepper. Bring the sauce to a boil, then lower the heat and cover. Slowly simmer for 1 1/2 to 2 hours, stirring now and then, until the sauce is very thick. Taste again for salt and pepper.
When you are ready to serve, bring a large pot of salted water to a boil, add the pasta and cook for 8 to 10 minutes or until tender yet firm (as they say in Italian "al dente"). Drain the pasta well and toss with the Bolognese sauce.
Serve with a good scoop of fresh ricotta cheese and garnish with some shredded basil, grated Parmigiano and a drizzle of olive oil.