Heat the oil in a large saucepan over a medium–high heat. Add the fennel and sliced red onion, along with a big pinch of salt. Cook, stirring regularly, for 5 minutes, then add the aubergine. Cook for a further 10 minutes until all the veg has collapsed and softened, and is a little caramelised.

Scrape in the garlic and fennel, along with the chilli, if using, and cook for 1 minute more, then tip in the tomatoes. Half-fill the can with water, and pour that in too. Tip in your beans, along with their bean stock (this thickens the sauce). Chuck in a Parmesan rind, if you have one. Leave to bubble away for 10–15 minutes while you make the vinaigrette.

In a small bowl, mix the chopped red onion with the capers and vinegar. Add the olive oil and season to taste – it should be tangy, so add some more vinegar if needed.

Mix the remaining ½ chopped red oil in a small bowl with the capers and vinegar. Add a good slosh of olive oil (you want about 3 tbsp) Season the vinaigrette to taste - it should be tangy, so add some more vinegar if it needs.

Season the stew to taste, then ladle into bowls. Serve topped with the caper vinaigrette, grated Parmesan and basil leaves.