To prepare the chestnuts: wash them, put them in a saucepan with plenty of cold water (they must be completely covered) and a pinch of salt, bring to the boil and cook for approximately 45 minutes. Then strain them and peel them before they cool down too much, this makes it easier to remove the thin inner skin.
Clean the porcini mushrooms with a knife and then delicately rub them with a damp, wrung-out cotton cloth. Slice them thinly and set them aside. In a large heavy-bottomed frying pan (it will also have to contain the pasta), heat 3 spoonfuls of olive oil with the peeled cloves of garlic and, if you like, a chilli pepper. When the garlic has turned golden brown, remove it and add the sliced mushrooms and the cooked chestnuts, broken up coarsely. Stir and pour in the white wine; when it has evaporated, season with salt, sprinkle with parsley (just the leaves, washed, patted dry and chopped) and continue cooking for a few more minutes. Turn the heat off, put the lid on the pan and keep it warm. Cook the slices of pancetta in a small heavy-bottomed frying pan, then place them on absorbent paper to remove any excess fat and make them nice and crispy. Cook the pasta in plenty of boiling, salted water; strain when “al dente” and toss it in the frying pan with the sauce for a couple of minutes over a lively heat. Stir well to amalgamate everything, garnish with the chopped pancetta and serve the pappardelle immediately while nice and hot.