Fill a large pot with 8 cups water and bring it to a boil.
Add ½ tablespoon salt, ½ of the onion, 3 garlic cloves, and 2 bay leaves. Add 2 –3 lbs bone-in chicken and cook for about 25 minutes, or until fully cooked. Skin any foam off the top of the water while the chicken is cooking.
When the chicken is done cooking, remove the chicken and set aside, reserving the broth.
Remove the stems and seeds from the 5 mulato chiles, 6 pasilla chiles, and 3 chipotle chiles and reserve the seeds. Heat a skillet over medium heat and lightly toast the chiles for about 10–20 seconds per side until fragrant. Be careful not to burn them.
Transfer the chiles to a bowl and cover with warm water. Let them soak for 15–20 minutes until softened.
In the same dry skillet, toast 1 cinnamon stick, 3 whole cloves, ¾ tsp coriander seeds, ½ tsp cumin seeds, ½ tsp peppercorns, and 1 tsp of the reserved chili seeds until fragrant. Remove from the pan.
Place the whole spices in a spice grinder and blend until they ground.
Dry toast ¼ cup sesame seeds until lightly golden and remove.
Add about 3 cups of the reserved chicken broth to a food processor. Set aside, and after you prepare each ingredient, place them in the food processor.
Add 3 tablespoons of vegetable oil to the skillet over medium heat. Fry ¼ cup raisins until they puff up, then remove them and place in the food processor.
Fry 8 galletas Marias until lightly toasted, then remove them and place in the food processor.
Fry 1 ripe plantain slices until lightly caramelized, then remove them and place in the food processor.
Doing each nut separately, fry ¼ cup almonds, ¼ cup peanuts, ¼ cup pecans, and 2 tbsp pepitas until lightly browned and fragrant, then remove them and place in the food processor.
Toast 1 corn tortilla in the skillet until crisp and put in the food processor.
Lightly char the remaining ½ onion and place it in the food processor.
Lightly fry the remaining 5 garlic cloves until fragrant. Transfer everything to the food processor.
Drain the soaked chiles and add them to the food processor along with the toasted spices, and ¾ of the toasted sesame seeds. Blend until completely smooth.
Heat about ½ cup of vegetable oil in a large pot over medium heat. Carefully pour the blended mole sauce into the pot and stir constantly over low heat as it begins to thicken.
Once the sauce has heated up, add 1 Mexican hot chocolate drink tablet and 2 oz piloncillo, stirring until they melt completely.
Bring the mole to a gentle simmer and cook for at least 30 minutes, stirring occasionally. You can add another ½ - 1 cup of chicken broth to the sauce if it gets too thick too quickly. For deeper flavor, it can simmer for up to 2–3 hours. Season with salt to taste.
Plate the warm, unsauced chicken, and then pour the mole sauce over the top.
Garnish with toasted sesame seeds and serve with rice and tortillas. Enjoy!