• 1 ripe, medium-size plantain, peeled and cut into 1/4 - inch dice.
For finishing the sauce:
• 1 to 1 1/2 cups milk
• 1 slice firm white bread, crusts removed
• 1 tablespoon sugar
• Salt, about 1/2 generous teaspoon
• 1 teaspoon dry sherry
• 1/4 teaspoon cinnamon, preferable freshly ground Mexican canela
• 1/2 cup heavy (whipping) cream or Mexican crema
For the garnish:
• 1 pomegranate
• 8 sprigs flat-leaf parsley
1. Peeling the walnuts. If using mature-green walnuts, break away the soft, green, outer layer with your hands. Working with 5 or 6 at a time, crack open the nuts, remove the meats in the largest pieces possible. Drop the walnut pieces into a small pan of boiling water, immediately remove with a slotted spoon to a paper towel, then peel: the thin, brown skin that covers each piece will peel off in fairly large pieces if the nuts are very fresh; use a small pick or pointed trussing needle to help lift the skin out of the crevices. Continue until all are peeled. Store the nuts in a tightly-sealed jar, refrigerated, until ready to use.
2. Cooking and shredding the meat. Place the pork in a medium saucepan, cover with heavily salted water, add the garlic and half of the onion. Bring to a gentle boil over medium heat, skim off any grayish foam that rises to the surface, partially cover and simmer over medium-low until the meat is thoroughly tender, about 1 1/2 hours.
If time permits, let the meat cool in the broth, then remove it with tongs or a slotted spoon and shred it between you fingers or with two forks held back to back. (There will be about 2 cups of meat). Reserve the broth.
3. Roasting the chiles. The open flame method: Place chiles directly over the gas flame or on a medium hot charcoal or gas grill. Roast, turning occasionally, until blistered and blackened on all sides but not soft, about 5 minutes. The broiler method: Lay chiles on a baking sheet set about 4 inches below a preheated broiler. Roast, turning occasionally until blistered and blackened on all sides but not soft, about 10 minutes. Peel the charred skin off the chiles and rinse them if necessary. Make a long slit in the side of each chile and carefully remove the seeds and veins.
4. The stuffing. Before you start cooking, complete all the initial peeling, coring, chopping and so forth of the stuffing ingredients (a little oxidizing of the apples and pears won't spoil the appearance of the dish.)
Heat 1 1/2 tablespoons of the oil in a very large (12 inch) skillet over medium-high. When quite hot, add the remaining half of the onion and shredded pork in a thin layer and cook, stirring frequently, until the mixture is lightly browned, 8 to 10 minutes. Drain off any excess fat.
Stir in the raisins, candied fruit, pear, apple, peach, the tomato, herbs and cinnamon. Measure in 1/4 cup of the reserved broth, mix well, reduce the heat to medium-low, cover the skillet and simmer until the apple and pear are tender (but not mushy) and the flavors are blended, about 10 minutes. Season with salt, usually a generous teaspoon.