Heat the vegetable oil in a large pot or Dutch oven over medium heat. Add the diced onion and a portion of the kosher salt. Stir occasionally and cook until the onion becomes soft and translucent, about 5 minutes.
Stir in the chopped chiles, cocoa powder, smoked paprika, ancho chili powder, oregano, cumin, cinnamon, and allspice. Cook for 1 to 2 minutes, stirring frequently, until the spices are fragrant and well-toasted.
Add the ground meat to the pot, breaking it apart with a wooden spoon. Cook, stirring occasionally, until the meat is thoroughly browned and no longer pink, approximately 5 to 7 minutes.
Introduce the diced tomatoes, stout beer, and stock to the pot. Increase the heat to bring the mixture to a boil, then reduce to a gentle simmer. Let the chili cook for 15 to 20 minutes, allowing the flavors to meld and the liquid to slightly reduce.
Lower the heat further and stir in the pinto beans, chopped chocolate, and smooth peanut butter. Continue stirring until the beans are heated through, and the chocolate has fully melted, about 5 minutes. Adjust the seasoning with additional salt, if needed.
Serve immediately, garnished with your choice of tortilla chips, shredded cheese, or diced avocado, as desired.