Put the beef mince, half the chilli spice mix and the onion in a large bowl. Mix together with your hands and then shape into 24 small meatballs.
Heat a wide deep saucepan and spray with the cooking spray. Cook the meatballs in batches for 10 minutes, turning occasionally until browned all over and almost cooked. Remove and set aside.
Spray the pan again with the cooking spray and add the chilli, tomato puree and remaining spice mix. Cook for 1 minute. Stir in the tomatoes and stock and bring to the boil. Simmer for 10 minutes, stirring occasionally.
Return the meatballs to the pan and stir in the black beans. Simmer for a further 5 minutes until the sauce is thickened and the meatballs are cooked. Check the seasoning and serve immediately.
To complete the fiesta, serve with dried brown rice, cooked according to the packet instructions, guacamole and soured cream.