Warm the oil in a large pot and brown the sausages on both sides (can be done in batches if needed).
Stir in the onion and allow to cook for 5 minutes then add the garlic.
Add all the other ingredients to the pot, bring to the boil then reduce the heat and allow to simmer for 60 minutes.
The beans will start to break down during cooking and will help to thicken the sauce.
Serve with brown rice and veggies.