Creamy and cheesy leeks with Cheddar and a golden, crispy breadcrumb crust. Serve this bubbling bake as a side dish for your Sunday roast or as a delicious vegetarian main dish.
I make this easy cheesy leeks recipe regularly; it’s the kind of dish suitable for many purposes. It’s not only perfect when served with a festive pork roast but also delicious as a meal on its own, a vegetable bake that my kids look forward to eating.
Tender leeks smothered in a smooth cheesy sauce; this is one of my favorite ways of enjoying leeks, and I love leeks cooked in any possible way! Check out these Roasted Leeks, the Buttered Leeks, or the Pea Frittata with Leeks (and Parmesan).
- Leeks: I recommend weighing the leeks after trimming them; you will need about 500-600 g/ 1.1-1.3 lbs. Those would be about three leeks around here, but leeks can come in various sizes, so it’s always a good idea to weigh them.
- Cheese: Cheddar cheese is always my first choice, but if you like, you can use another strong-flavored, good-melting cheese. Gruyere or Gouda are always suitable substitutes.
- Panko breadcrumbs: While the dish will still be delicious when topped with regular breadcrumbs, I find them a bit better; they are larger and thus crunchier.
- Butter, flour, and milk.
- Mustard: I use either Dijon mustard or regular yellow mustard.
- Spices: Fine sea salt and ground black pepper, nutmeg, dried thyme, or any other herbs you like. Fresh thyme leaves are also great if you have them.
How to bake leeks in cheese sauce?
Prepare the leeks
- Top and tail them.
- Clean them thoroughly. Dirt collects between the many layers of leaves, especially at the transition from the white part to the green part of the vegetable. Separate the layers and thoroughly wash in between the layers.
- Cut the plants into 1 inch/ 2 ½ cm slices (1).
- Boil: Bring a large pot of water to a boil. Add salt and the leeks. Cook for 7-8 minutes or until tender but not mushy; drain them in a colander (2).
Cheese sauce recipe
- Melt the butter in a medium saucepan on medium to low heat.
- Sprinkle the plain flour into the pan and roast shortly until lightly golden, about 1 minute (3).
- Slowly add the milk while whisking continuously to avoid the formation of clumps. Whisk until the white sauce is smooth and creamy and coats the back of a spoon. It will take a couple of minutes (4).
- Combine: Stir in the mustard, nutmeg, and ¾ of the grated cheese (5). Stir until the cheese is melted; add the cooked leeks and stir to combine (6).
- Adjust the taste with salt and pepper.
Assemble and bake
- Pour the cheesy leeks into a buttered baking dish (7).
- Mix the panko breadcrumbs with the dried thyme and the remaining cheese (8).
- Sprinkle the cheesy breadcrumbs over the vegetables (9).
- Bake the cheese leeks in the preheated oven for about 20-25 minutes or until nicely golden (10).
- Rest for 5 minutes and serve.
- Make sure you clean the leeks thoroughly; the dirt finds its way everywhere between the layers, and you must get it all out.
- Don’t use pre-grated cheese; it contains additives that will prevent the cheese from melting nicely.
- Our favorite recipe variation: Replace ⅓ of the leeks with frozen peas. You don’t have to defrost the peas; just stir them as they are into the leek and cheese sauce mixture.
Yes. Choose strongly-flavored and good-melting sorts like Gouda, Gruyere, Comte, or Swiss.
Yes. Prepare and assemble the cheesy leeks casserole. Let the dish cool completely, cover it with plastic wrap and refrigerate it until ready to bake.
Refrigerate in an airtight container for 3-4 days.
Reheat in the microwave or the oven before serving.
I don’t recommend freezing; the cheese sauce will not be so nice once defrosted.
How to serve?
The cheesy leeks can be served as a vegetarian main dish. Serve it with mashed or boiled potatoes, crusty bread, polenta, rice, bulgur, etc.
Or serve the leeks in creamy cheese sauce as a delicious side dish for your roast dinner. Try them with this Balsamic Beef (in the Dutch Oven), Roasted Leg of Lamb, or Slow-Cooked Lamb Shoulder Recipe.
More cheesy vegetable bakes
Creamy Cheesy Leeks
- Baking dish about 10x6 inches/ 26x15 cm
- 1.8-2 lbs leeks 850 g/ 28-31 oz, Notes 1,2
- 2 tablespoons butter 30 g/ 1 oz
- 3 ½ tablespoons all-purpose flour 30 g/ 1 oz
- 1 ½ cups full-fat milk 350 ml/ 12 fl.oz
- 2 teaspoons Dijon mustard
- ¾ teaspoon fine sea salt or Kosher more to taste
- ½ teaspoon freshly ground black pepper
- ⅛ teaspoon nutmeg
- 1 ½ cups Cheddar grated, 100 g/ 3.5 oz, Note 3
- 6 tablespoons panko breadcrumbs
- ½ teaspoon dried thyme
- Preheat the oven to 350°F/ 180°C.
- Top and tail the leeks. Clean them thoroughly, and check for hidden dirt between the layers. Cut into 1 inch/ 2 ½ cm slices.
- Cook: Bring a large pot of water to a boil. Add salt and the leeks. Bring the water to a boil again and then cook the leeks for 7-8 minutes or until tender; they should be tender but not mushy. Drain in a colander.
- Roux: Melt the butter in a saucepan. Stir the flour into the pan and cook for about 1 minute until lightly golden.
- Slowly whisk in the milk. Whisk until the sauce is smooth and creamy and coats the back of a spoon, about 2-3 minutes.
- Combine: Add the mustard, nutmeg, and ¾ of the grated cheese. Stir until the cheese is melted; add the drained leeks and stir to combine. Adjust the taste with salt and pepper (Note 2).
- Assemble: Pour the cheesy leeks into a greased baking dish. Mix the panko breadcrumbs with the dried thyme and the remaining cheese. Sprinkle the mixture over the vegetables in cheese sauce.
- Bake in the preheated oven for about 20-25 minutes or until bubbly and nicely golden. Rest for 5 minutes and serve.
- Leeks can differ in size very much, that’s why I prefer to weigh them. I weighed the vegetables after trimming them.
- Replace about ⅓ of the leeks with frozen peas. No need to defrost them before adding them to the leek and cheese mixture.
- Sub Cheddar with other strong-flavored, good-melting cheese like Gouda, Swiss, Gruyere, and Comte. Don’t use pre-grated cheese; the additives it contains will prevent it from melting nicely.