In a large pot, cook the chopped bacon over medium heat until crisp, stirring often. Remove the bacon to a paper towel-lined plate and set aside.
In the same pot, add the chopped onion and bell pepper. Cook until softened, stirring occasionally.
Add the ground beef and cook until browned. Drain excess grease by tilting the pot and using a large spoon.
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 and stir to combine.
Simmer over medium-low heat for at least 45 minutes, stirring occasionally. For enhanced flavor, allow the chili to cook longer, adding extra beef stock or water if needed.
Serve hot, garnished with sour cream, shredded cheese, chopped cilantro, and the remaining bacon.