Equipment
Ingredients
Main
- 1350 g leeks, trimmed, washed, and halved
- 2 g salt, fine
- 1 g black pepper, ground
- 50 g unsalted butter
- 50 g all-purpose flour
- 425 ml whole milk
- 175 g cheddar cheese, grated
- 25 g parmesan cheese, grated
- 15 g wholegrain mustard
- 15 g dijon mustard
- 5 g english mustard
Topping
- 30 g breadcrumbs
- 25 g cheddar cheese, grated
Nutrition (per serving)
Method
Preheat the oven to 200°C (400°F).
Boil the leeks in salted water for 3 minutes until they are slightly tender.
Drain the leeks in a colander and rinse them with cold water to stop the cooking process.
Melt the butter in a saucepan over medium heat and whisk in the flour to create a smooth paste.
Slowly pour the milk into the saucepan, whisking constantly to prevent lumps from forming.
Bring the sauce to a boil, then reduce heat and simmer for 2 minutes until thickened.
Stir in the 175g of cheddar, parmesan, and the three types of mustard until the cheese has melted.
Season the sauce with salt and black pepper to taste.
Place the drained leeks into a shallow baking dish.
Pour the prepared mustard sauce evenly over the leeks.
In a small bowl, mix the breadcrumbs with the remaining 25g of grated cheddar.
Scatter the breadcrumb and cheese mixture over the top of the sauce.
Bake in the preheated oven at 200°C (400°F) for 20 minutes.
Chef's Notes
- For exceptionally tender leeks, ensure you trim off the tough dark green tops and thoroughly wash them to remove any grit trapped between the layers.
- When making the béchamel sauce, using cold milk added to the hot roux (butter and flour mixture) can help prevent lumps. Alternatively, ensure your milk is warm but not boiling before adding.
- The combination of three mustards – wholegrain for texture, Dijon for sharpness, and English for a kick – creates a complex flavour profile. Adjust the quantities based on your preference for heat and pungency.
- Don't overcook the leeks in the initial boiling stage; they will continue to cook in the oven. Aim for just tender, so they don't become mushy.
- For an even crispier topping, you can add a tablespoon of melted butter to the breadcrumb and cheese mixture before scattering.
Storage
Refrigerator: 3 days — Store in an airtight container.
Freezer: 1 month — Texture of leeks may soften significantly upon thawing.
Reheating: Reheat in an oven at 180°C (350°F) until bubbling.
