Heat the oil in a wide-based casserole dish or deep frying pan. Add the garlic, fennel seeds and chilli flakes, if using, and fry, stirring, on a medium heat for 30 seconds, then add the leeks, fennel and a teaspoon of flaky sea salt. Partially cover the pan and cook for 10 minutes, giving everything a stir every few minutes, until the leeks and fennel have softened.

Turn up the heat under the pan and take off the lid, so the leeks take on a little colour. Scrape the base of the pan – add a little of the vegetable stock to help dislodge any stuck-on bits, if need be – then add the beans and remaining stock. Bring to a boil, turn down the heat to a simmer and leave to cook for 20 minutes, topping up with extra stock if required.

Meanwhile, make the gremolata by mixing all the ingredients with a teaspoon of salt in a bowl.

Once the beans have had their 20 minutes, stir in the tahini and lemon juice, and add more stock if necessary to loosen to a sauce the consistency of single cream; you’re not after a soup here. Taste and adjust the salt as required, then spoon into warmed bowls, top with the date gremolata and serve with flatbreads on the side.