Chicken, leek and white bean casserole brings together tender chicken, sweet leeks and soft beans in a light, savoury gravy. It is a comforting supper that does not need a cream sauce: crushing a few of the beans into the cooking liquid gives the pot a pleasingly creamy texture of its own.
This version starts on the hob and finishes in the oven. Browning the chicken gives the gravy depth, while slowly softening the leeks draws out their sweetness. Mustard, thyme and a little lemon keep the finished dish lively. Serve it with bread or potatoes and something green alongside.
A casserole built around soft leeks and white beans
Boneless chicken thighs work well here because they stay tender during covered cooking. Cannellini beans are small enough to settle between the vegetables and soft enough to thicken the sauce when lightly crushed. Use tinned, cooked beans for this recipe; dried beans need separate preparation and cannot be substituted directly.
Serves: 4. Preparation: about 20 minutes. Cooking: about 55 minutes. You will need a wide casserole dish with a lid, suitable for both the hob and oven. Alternatively, begin in a frying pan and transfer everything to an ovenproof dish before baking.
Ingredients
- 600 g boneless, skinless chicken thighs, trimmed of excess fat
- 1 tablespoon olive oil
- 2 large leeks, about 400 g before trimming
- 2 medium carrots, cut into small half-moons
- 2 celery sticks, finely sliced
- 3 garlic cloves, finely chopped
- 1 tablespoon plain flour
- 500 ml reduced-salt chicken stock
- 2 teaspoons Dijon mustard
- 1 teaspoon dried thyme, or 4 small fresh thyme sprigs
- 1 bay leaf
- 2 x 400 g tins cannellini beans, drained and rinsed
- 100 g spinach
- Finely grated zest of half a lemon, plus 1 to 2 teaspoons lemon juice
- 2 tablespoons chopped flat-leaf parsley
- Freshly ground black pepper and a little salt, if needed
Prepare the ingredients
Trim the roots and tough dark green leaves from the leeks. Split the white and tender pale green parts lengthways, then rinse between the layers under running water to remove grit. Slice into half-moons about 1 cm thick and let them drain while you prepare the other vegetables.
Pat the chicken dry with kitchen paper to help it brown. Keep raw chicken and its utensils away from prepared vegetables, and wash your hands and equipment after handling it. There is no need to wash the chicken. Drain and rinse the beans, and roughly chop any large spinach leaves.
How to make the casserole
- Heat the oven. Set it to 180 degrees Celsius, or 160 degrees Celsius fan. Put the casserole dish over a medium-high heat and add the olive oil. Season the chicken with black pepper and a small pinch of salt, if using.
- Brown the chicken. Cook the thighs for about 3 minutes on each side until lightly golden. Work in batches if the dish is crowded. Transfer to a plate; the chicken will still need further cooking.
- Soften the vegetables. Reduce the heat to medium-low. Add the leeks, carrots and celery, with a splash of water if the base is dry. Cook for 10 to 12 minutes, stirring regularly, until the leeks soften. Add the garlic and cook for another minute.
- Make the gravy. Stir in the flour and cook for a minute. Gradually pour in the stock, stirring and scraping up the golden bits from the bottom. Add the mustard, thyme and bay leaf, then bring to a gentle simmer.
- Bake with the lid on. Return the chicken and any juices from the plate to the dish. Nestle the thighs among the vegetables, cover and bake for 25 minutes.
- Add the beans. Stir the beans into the liquid around the chicken. Cover again and bake for another 10 to 15 minutes, until the carrots are tender and the chicken is cooked through. Check the thickest part with a clean food thermometer if available, following its poultry guidance. Allow extra cooking time if needed.
- Finish the sauce. Remove the bay leaf and any thyme stalks. Crush a spoonful of beans against the side of the dish and stir them into the liquid. Fold in the spinach and warm over a low hob heat for 2 to 3 minutes, covered, until wilted and hot.
- Add the final flavours. Stir in the lemon zest, parsley and 1 teaspoon lemon juice. Taste before adding more lemon, pepper or salt. Let the casserole rest for a few minutes before serving.
Adjusting the sauce
If it seems too thin
The gravy should lightly coat the ingredients, with enough liquid to spoon around the chicken. Mash another spoonful of beans into it for more body. You can also simmer the casserole uncovered for a few minutes, stirring carefully so the beans do not catch on the bottom.
If it becomes too thick
Add a small splash of hot water or stock, stir and check again. Different dishes lose different amounts of moisture, especially if the lid fits loosely. The sauce also thickens a little as it rests, so stop reducing it while it still looks slightly loose.
What to serve alongside
Wholemeal bread is useful for soaking up the gravy, while boiled new potatoes make a lovely addition to the bowl. A small serving of brown rice also works. The beans already give the casserole plenty of substance, so choose an accompaniment that suits your appetite.
For a green vegetable, try steamed broccoli, green beans or shredded cabbage. Keep the seasoning simple so the leeks remain the main flavour. If some people prefer a milder finish, leave the lemon juice out of the pot and let everyone add a little to their own bowl.
Simple variations
- Use butter beans: replace the cannellini beans with the same quantity of drained butter beans. Stir gently to keep the larger beans intact.
- Swap spinach for kale: remove tough stalks from 100 g kale and shred the leaves finely. Add with the beans so it has time to soften in the oven.
- Add mushrooms: brown 200 g sliced mushrooms after removing the chicken. Let their released liquid evaporate before adding the leeks and other vegetables.
- Try a creamy finish: stir in 2 tablespoons of creme fraiche off the heat. Taste before adding lemon juice, since it brings its own tang.
Storage and reheating
Divide leftovers into shallow containers to help them cool promptly, then refrigerate within two hours. Eat within 48 hours. Reheat only the portion you need in a covered saucepan, adding a splash of water to loosen the sauce. Stir and turn the chicken until everything is steaming hot throughout, including the centre of each thigh.
Freeze cooled portions for up to three months if you want to keep them longer. Label the containers and leave a little space for expansion. Defrost in the fridge before reheating, and reheat only once. The beans may soften further after freezing and make the sauce thicker. Add a little water as needed and finish with fresh parsley if you have some.
