Prepare the onion, carrot, celery and red pepper and set aside.
Mix garlic, thyme, Cajun spice mix and paprika and set aside.
Cut sausages.
Heat 1 tbsp of the oil in a large flame-proof casserole dish on a medium heat. Carefully lower the sausages into the pan (you may have to do this in batches so you don’t overcrowd the pan). Cook on all sides for 4-5 mins, or until deeply golden. Remove from the pan and set aside on a plate – you’ll finish cooking them later.
Combine the prepared onion, carrot, celery and red pepper to the pan. Cook with a pinch of salt for 15-20 mins, stirring regularly until caramelised and golden around the edges.
Tip in the mixed garlic, thyme, Cajun spice mix and paprika, and cook for 3-4 mins.
Pour in the canned tomatoes, stock and beans. Bring to the boil, then return the sausages to the pan. Cook for 30 mins on a medium heat until slightly reduced and bubbling.
Serve with crusty bread.
To freeze, leave to cool completely and transfer to a freezer-proof container. Will keep frozen for up to three months. To reheat, tip into a large flame-proof casserole dish and thaw on a low heat. Once mostly defrosted, turn the heat up to medium, stirring often, until piping hot.