Heat the butter or olive oil in a large pot over a low heat. Stir in the onion and capsicum with a large pinch of salt and cook until very soft, about 10 minutes.
Sir in the chorizo and cook for 5 minutes, until lightly browned.
Add garlic, spices and beef mince. Stir, breaking the beef apart, and cook until the beef is brown all over.
If using fresh tomatoes roughly dice them.
Add the beef broth, tomatoes and tomato paste. Bring to a boil and then simmer uncovered, stirring occasionally, for 30 minutes.
Season with salt and pepper to taste and stir in the coriander leaves.
Serve with avocado slices or guacamole*, sour cream or yoghurt, lime wedges and salad leaves. Also delicious with corn tortillas or on top of rice.