Brown the sausages and bacon under the grill preheated to 200C. For the best results use the fan assisted grill setting:Space the sausages on an oven tray and leave small gaps in between them. Grill them on the middle shelf for 8 minutes. Next, turn them over, add pieces of bacon and insert the tray back to the oven for 10 more minutes.(Hairy Bikers recommend frying sausages with a little bit of oil in a non-stick frying pan for 10 minutes, turning regularly.) While the sausages are in the oven, start preparing the sauce. Heat up a few tablespoons of oil in the shallow cast iron pot, add the onion in and fry until soft and opaque, around 5 minutes.
Add the garlic into the cast iron pot and fry with onion for 2 - 3 more minutes, until the onion is lightly golden.
Sprinkle in the chilli powder/smoked paprika, give it 3 - 4 stirs.
Quickly add tomatoes, tomato puree, Worcestershire sauce, brown sugar, salt and herbs (to stop paprika from burning).
Pour in the stock and wine (or the same amount of water if you are not using wine) and bring to a gentle simmer and give it a good stir.
Transfer browned sausages and bacon from the tray to the sauce. Reduce the heat to low - medium and gently simmer for 20 minutes. Don't close the lid completely, leave a gap so the steam can escape, stir from time to time.
After approximately 20 minutes stir in the beans and cook for additional 10 minutes. Keep the heat on low - medium. This time leave the pot uncovered so more steam can escape.
If you prefer the sauce thicker, you can extend the cooking time 5 - 8 minutes to let more liquid evaporate.
Adjust the casserole taste with salt if needed and season with pepper (optional).
Serve with bread, rice or mash.