Directions

• Bring 8 cups of water and 1/2 tablespoon of salt to a boil in a large stockpot over high. Reduce heat to medium-low and add chicken. Cook until the chicken is tender and a thermometer inserted in the thickest portion of the meat registers 155°F, about 30 minutes. Remove chicken; set aside on a large plate. Reserve 4 cups of the chicken cooking liquid in a large heatproof bowl; discard remaining cooking liquid.
• Heat 1/4 cup vegetable oil in a 12-inch skillet over medium-high. Add 8 garlic cloves; cook, stirring constantly, until fragrant, about 1 minute. Add tomatoes, onions, and 1/2 tablespoon salt; cook, stirring occasionally, until onions are translucent and softened, about 8 minutes. Transfer mixture to a blender. Secure lid on blender and remove center piece to allow steam to escape. Place a kitchen towel over opening on lid. Process until smooth, about 1 minute. Transfer mixture to a large bowl and set aside.
• Wipe skillet clean. Add 3 cups vegetable oil; heat over medium-high. Working with a few different types of chiles at a time, place in a spider and submerge in hot oil for 2 seconds per batch. Remove from oil using spider and place in a large heat-proof bowl. Repeat with remaining chiles and remaining four garlic cloves.
• Place sesame seeds and pepitas in a medium metal strainer; submerge in hot oil in skillet over medium-high. Cook, stirring mixture inside strainer and shaking occasionally, until seeds are golden brown and fragrant, about 2 minutes. Transfer seed mixture to bowl with chile mixture.
• Working with one tortilla at a time, add to hot oil in skillet over medium-high. Cook, turning occasionally, until golden brown, 30 seconds to 1 minute. Transfer fried tortillas to a plate lined with paper towels; let cool 5 minutes. Break into 2-inch pieces. (Strained and cooled oil may be reused for frying.)
• Add chile mixture, tortilla pieces, and bolillo pieces to reserved 4 cups chicken cooking liquid in bowl. Let stand until liquid is almost absorbed and bolillo has softened, about 10 minutes. Transfer mixture to a blender; process until smooth, about 1 minute.
• Heat remaining 1/2 cup vegetable oil in a large pot over medium. Add tomato mixture; cook, stirring constantly, until heated through, about 1 minute. Add blended chile mixture and chocolate disk. Bring to a simmer over medium-high. Cook, stirring occasionally, until chocolate has melted and mixture is well combined, about 20 minutes. Add cooked chicken and remaining 1 tablespoon salt; stir to submerge in mole. Reduce heat to medium-low; cover and simmer until chicken is heated through, 10 to 15 minutes. Serve with rice and tortillas; garnish with additional sesame seeds.