Heat oil in a heavy pot over medium-high. Add onion, capsicum and a pinch of salt. Cook 6 minutes until soft.
Add garlic, cumin, paprika, oregano, coriander and cocoa. Stir for 60 seconds until fragrant.
Add beef mince. Break up with a wooden spoon. Cook 8 minutes until browned and the liquid has cooked off.
Stir in chili powder, tomato paste, diced tomatoes, both beans and beef stock. Bring to a simmer.
Reduce heat to low. Cover with the lid askew. Simmer 40 minutes, stirring every 10.
Taste. Adjust salt, pepper, and chili powder. If watery, simmer uncovered another 10 minutes.
Serve hot with grated tasty cheese, sour cream, sliced jalapeno, chopped coriander and lime wedges.