In a large pot, cook the chopped bacon over medium heat until crispy, stirring occasionally. Remove the bacon with a slotted spoon and place it on a paper towel-lined plate. Set aside.
Add the chopped onion and bell pepper to the pot with the bacon drippings. Cook until softened, about 5 minutes, stirring occasionally.
Add the ground beef to the pot and cook until browned. Drain excess grease by tilting the pot and using a spoon to remove it.
Stir in the kidney beans, pinto beans, black beans, fire-roasted tomatoes, tomato paste, jalapeño, beef stock, oregano, cumin, cocoa powder, kosher salt, black pepper, smoked paprika, ground coriander, chili powder, Worcestershire sauce, and garlic.
Add ¾ of the cooked bacon back into the pot and stir everything to combine.
Simmer over medium-low heat for at least 45 minutes, stirring occasionally. For enhanced flavor, let it cook longer (up to several hours), adding extra beef stock or water if needed to maintain the desired consistency.
Serve hot, garnished with sour cream, shredded cheese, chopped cilantro, and the remaining crispy bacon.