Ingredients

• 5 ounces (3 medium) tomatillos, husked and rinsed
• ½ cup (about 2 ½ ounces) sesame seeds
• About ½ cup rich-tasting pork lard or vegetable oil, plus a little more if necessary
• 6 medium (about 3 ounces total) dried mulato chiles, stemmed and seeded
• 3 medium (about 1 ½ ounces total) dried ancho chiles, stemmed and seeded
• 5 medium (about 1 ½ ounces total) dried pasilla chiles, stemmed and seeded
• 4 garlic cloves, peeled
• A scant ½ cup (about 2 ounces) unskinned almonds
• ½ cup (about 2 ounces) raisins
• 1 whole (about 4 pounds) boneless turkey breast with skin on, the two halves cut apart, any netting removed (some brands sell individual turkey breast as a 2-pound roast—you’ll need two of them)
• Salt
• ½ teaspoon cinnamon, preferably freshly ground Mexican canela
• ¼ teaspoon black pepper, preferably freshly ground
• ¼ teaspoon anise seed, preferably freshly ground (optional)
• A scant 1/8 teaspoon cloves, preferably freshly ground
• 1 slice firm white bread, darkly toasted and broken into several pieces
• 1 ounce (about 1/3 of a 3.3-ounce tablet) Mexican chocolate, roughly chopped
• 4 to 5 tablespoons sugar
• Sprigs of watercress or fresh flatleaf parsley, for garnish

Procedure

1. Getting started. To ensure success and to streamline a rather complex preparation, first set out all the ingredients, completing basic preparations as described: husk and rinse the tomatillos, stem and seed dried chiles, peel the garlic, grind spices if you’re using whole, toast the bread and chop the chocolate.
2. Spread the tomatillos on a baking sheet and roast them 4 inches below a very hot broiler, until darkly roasted, even blackened in spots, about 5 minutes. Flip them over and roast the other side, 4 or 5 minutes, until splotchy-black, blistered and soft. Set out 2 large bowls and scrape the tomatillos, juice and all, into one of them. Set out a pair of tongs and a slotted spoon.
3. Initial toasting and browning. In an ungreased small skillet set over medium heat, toast the sesame seeds, stirring constantly until golden, about 5 minutes. Scrape 2/3 of them in with the tomatillos; set the rest aside for garnish.
4. Set a large (8- to 9-quart) pot (preferably a Dutch oven or Mexican cazuela) over medium heat. Measure the lard or oil into the pot. Turn on an exhaust fan or open a window or door. Tear the chiles into flat pieces and, when the lard or oil is hot, fry the chiles, three or four at a time, flipping them nearly continually with the tongs, until their interior sides have changed to a lighter color, about 20 to 30 seconds total frying time. Don’t toast them so darkly that they begin to smoke—that will make the mole bitter. As they’re done, remove them to the empty bowl, being careful to drain as much fat as possible back into the pot. Cover the toasted chiles with hot tap water and place a small plate on them to keep them submerged. Let stand about 30 minutes.
5. Meanwhile, remove any stray chile seeds left in the fat. With the pot still on the heat, fry the garlic and almonds, stirring regularly until browned (the garlic should be soft, the almonds browned through), about 5 minutes. With the slotted spoon, remove to the tomatillo bowl, draining as much fat as possible back into the pot. Now, add the raisins to the hot pot. Stir with your slotted spoon for 20 to 30 seconds, until they’ve puffed and browned slightly. Scoop them out, draining as much fat as possible back into the pot and add to the tomatillos.
6. Raise the temperature under the pot to medium-high. Sprinkle all sides of the turkey breast halves with salt, then lay one in the pot. Thoroughly brown it on all sides, about 10 minutes total. Remove to a clean plate; brown the other half in the same way. Cover and refrigerate if not completing Steps 3 and 4 within an hour or so. Set the pot aside.
7. Blending and straining. Use tongs to transfer the rehydrated chiles to a blender, leaving the soaking liquid behind. Taste the soaking liquid, and, if it is not bitter, measure 2 ½ cups into the blender. If it is, throw it away and measure in 2 ½ cups water. Blend the chiles to a smooth puree, adding a little extra water if necessary to keep the mixture moving through the blades. Press the chile mixture through a medium-mesh strainer back into the empty chile-soaking bowl. Without washing the blender jar, scrape the tomatillo mixture into it. Add 1 cup water, along with the cinnamon, black pepper, optional anise, cloves, bread and chocolate. Blend to a smooth puree, again adding a little extra water if necessary to keep the mixture moving. Press through the strainer back into the tomatillo bowl.