Step-by-step method:

Bring a large pot of water to the boil, add salt and pasta sheets one by one. Boil for fifteen minutes, stirring occasionally. When cooked, remove with a straining spoon and put into cold water.

After a few minutes, lay out on a cloth ready to fill. Preparing the filling. Brown the chopped meat and the chicken breast in a pan, with a little oil. Add the liver and the finely chopped onion, and brown. Add the sieved tomatoes and the wine, and cook for a few minutes to let the wine evaporate.

Finally, add the well-cleaned brain, and salt and pepper to taste.

When cooked, mince the meat.Warm the butter in a pan, add the flour and brown gently, then add the milk. Return the mince to the pan, along with the minced truffle, and cook for 5 minutes. Remove from the heat and leave to cool on a baking tray. Fill each pasta sheet with a little filling and roll up. Put the cannelloni next to each other in a baking dish with the béchamel, and cover with the remaining béchamel sauce.

Preparing the sauce:

Melt the butter in a pan, add the flour and cook gently, stirring constantly with a spoon. Without removing from the heat, add the milk and beat well, to prevent any lumps forming. Cook on a low heat, stirring constantly, until the sauce thickens. Add salt and pepper and a little nutmeg. Put some of the sauce in the baking dish and the cannelloni on top. Cover with the remaining sauce.

Cover the pasta with grated cheese and return to the oven until the cheese is golden brown.