Crush the bread to fine crumbs or grind in a food processor. You should have about 1 cup.
Wash and griddle-dry the chiles. Place in a bowl, cover generously with boiling water, and let soak for at least 20 minutes.
Roast the garlic cloves. When cool enough to handle, peel and set aside.
Bring a small saucepan of water to a boil, add the tomato and onion, and cook over medium heat for 10 minutes. Remove the vegetables. Save ½ cup of the cooking liquid, let cool slightly, and place in a blender with the tomato, onion, and roasted garlic. Process until thoroughly puréed (about 2 minutes on high). With a wooden spoon or pusher, force the mixture through a medium-mesh sieve into a bowl. Set aside.
Grind the canela, peppercorns, cloves, dried herbs, and bay leaves together in an electric coffee or spice grinder or with a mortar and pestle. Set aside.
Drain the soaked chiles. Place in a blender (you don't have to rinse it) with the stock and process until smooth (about 3 minutes on high), stopping occasionally to scrape down the sides with a rubber spatula. With a wooden spoon or pusher, force the mixture through a medium-mesh sieve into the bowl with the tomato purée.
Now you are ready to combine and cook the ingredients. In a heavy medium-size saucepan, heat the lard over medium heat until rippling. Add the ground spices and cook for 2 minutes, stirring often. Stir in the tomato-chile mixture; cook, covered, for 10 minutes, stirring occasionally. Stir in the bread crumbs and cook for 2 minutes. If the sauce seems pasty, thin it with a little water or stock. Add the sugar; taste for seasoning and add a little more salt or sugar if desired.