Mix all the meatloaf ingredients in a large bowl, using a wooden spoon, spatula or, best of all, your hands. Make sure all the ingredients are very well mixed, then leave the mixture to rest for a good 15 minutes or more.

Form the mixture into a compact, elongated loaf, trying your best to eliminate any creases in the loaf. Then roll it in the dried breadcrumbs until the loaf is totally covered.

Heat a cast iron "Dutch oven" large enough to hold the loaf snugly, preferably oval, and add a generous amount of olive oil. Shallow fry the loaf in the oil over gentle heat until it is golden brown on all sides.

Add a garlic clove to the oil and, when the garlic begins to give off its aroma, drizzle the wine over the loaf, let it simmer for a minute as the wine boils off. Then turn the loaf over and repeat the procedure. Continue until the loaf has been anointed with wine on all sides.

Now come the tomatoes. Crush them with your hands as you add them to the pot. Cover the pot and let the meatloaf braise for a good 30 minutes.

While the loaf is braising, sauté the mushrooms separately in a bit of olive oil add them to the pot, nestling them beside the loaf. Cover the pot once again, and let the loaf braise for another 30 minutes.

After that time, take the loaf out of the Dutch oven and let it rest for at least 15-20 minutes. You can even let the loaf cool completely if you prefer. Do not skip this step, however; it is crucial to allow the loaf to come together and firm up a bit. If you don't, the loaf is likely to fall apart when you slice it.

When you are ready to serve your polpettone, reheat the sauce. (If you find it too fatty, skim off the excess fat with a large spoon and discard it.)

Make a bed of the sauce in a large serving dish. Slice the loaf, or as much as you think you'll need, and lay the slices and rest of the loaf over the sauce. Serve immediately, with any extra sauce in a separate bowl for those you want more.