In a small bowl, combine the chili powder, paprika, cocoa powder, cane sugar, ground Mexican oregano, ground cumin, ground coriander, red pepper flakes, ground black pepper, and kosher salt. Stir until combined and set aside.
Heat the olive oil a large skillet over medium-high heat. Add onion and cook until translucent, about 4 minutes. Add garlic and cook briefly, about 1 minute longer. Pour the onions and garlic into the slow cooker crock.
Return the skillet to the stove and add the ground beef. Cook until the beef is brown. Turn off the heat, drain the fat, and add the cooked beef to the slow cooker crock.
Add the seasoning mix, tomato sauce, diced tomatoes, and diced green chiles to the slow cooker crock and stir to combine.
Place the cover on the slow cooker and cook the chili on high for 3-4 hours, or low for 6-8 hours.
Add the beans, stir to combine, and cook until heated through, about 15 minutes more. Taste and adjust seasoning if needed.
Serve warm with toppings of choice. Serves 8.