How to Make It
Preheat the oven to 350°. In a large bowl, combine the bread pieces with the milk and mash to a paste. Add the whole egg, egg yolk, chopped parsley, sage, thyme, salt, black pepper, nutmeg and cayenne and stir until smooth. Add the Parmigiano-Reggiano and dry bread crumbs and stir until thoroughly combined.
In a medium skillet, melt the butter. Add the onion and cook over moderate heat until softened, about 7 minutes. Add the garlic and cook just until fragrant, 1 minute longer. Let cool, then transfer to the bowl. Add the lamb, pork and veal and knead until evenly combined.
Brush a medium oval baking dish with oil. Transfer the meat loaf mixture to the dish and pat it into a 4-by-12-inch oval loaf. Bake for about 50 minutes, or until firm but not quite cooked through.
Meanwhile, in a medium saucepan, combine the red wine with the sugar, chopped tomato, molasses and allspice and bring to a boil over moderate heat, stirring to dissolve the sugar. Boil until the glaze is thick and syrupy, about 15 minutes.
Brush half of the glaze over the meat loaf. Continue baking for about 20 minutes longer, until an instant-read thermometer inserted in the center registers 150°; brush once more with the remaining glaze during baking. Let the meat loaf rest for 15 minutes, then thickly slice and serve.