Heat one tablespoon of oil in a large ovenproof casserole over a medium heat and cook the sausages until brown all over. Remove from the pan and set aside.
Add the remaining oil then the shallots and fry for 5 minutes until the shallots are beginning to brown. Add the garlic and cook for a further 2 minutes. Add the carrots and leeks and fry for a further 10 minutes then mix in the fennel seeds and bay leaves and pour over the cider. Bring to a boil for 3 minutes then reduce to a simmer and return the sausages with the lid on.
Cook for 20 minutes then add the butterbeans and cook for a further 10 minutes until the vegetables are all cooked but still have some bite. Taste for seasoning.
Spoon into warmed shallow bowls and serve with mashed potato or crusty bread.