Mix ground beef with chorizo meat, garlic, parsley and eggs. Add salt and pepper. Form into meatballs about the size of walnuts. Coat evenly with flour then reserve 1/3 cup flour and discard the rest. Fry the meatballs in the oil until evenly browned. Remove with a slotted spoon and set aside. Transfer 1/2 cup of oil to a skillet and fry the onion until golden. Sprinkle flour evenly over the onions and cook until lightly browned. Add tomato, the pepper, cinnamon stick and paprika. Cook for 5 minutes. Add stock and bring to a boil. Simmer for 5 minutes. Add meatballs and olives, partially cover and simmer for 30 minutes.