Dessert

Easy Cheesy Leek Bake Recipe

ByBen Miller January 27, 2026January 27, 2026

Introduction

Easy cheesy leeks is a comforting, creamy bake that makes the most of tender, caramelized leeks combined with a rich cheese sauce. It’s a perfect side dish or a satisfying vegetarian main that’s simple to prepare and full of flavor.

A round white ceramic dish holds a baked casserole with two main layers visible: the bottom layer is a creamy, pale yellow mixture with small chunks, likely vegetables or pasta, and the top layer is a thick, golden-brown breadcrumb crust that looks crunchy and slightly uneven. One section of the crumb topping is missing, revealing the creamy layer underneath. A woman's hand is holding a white plate above the dish, while the surface underneath the casserole is covered with a white marbled texture. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1 tbsp olive oil
20g butter, plus extra for the tin
6 leeks, washed and finely sliced
2 garlic cloves, bashed and peeled but left whole
10g thyme sprigs
50g parmesan or vegetarian alternative, finely grated
50g fresh breadcrumbs
20g butter
20g plain flour
300ml whole milk
½ whole nutmeg, grated
1½ tbsp Dijon mustard
75g gruyère or vegetarian alternative, grated
150g mild cheddar, grated

Instructions

Step 1: Set a large, deep pan over medium-low heat and warm the olive oil and 20g butter. When foaming, add the leeks, garlic, thyme, and a generous pinch of salt.
Step 2: Cook for 25-30 minutes with the lid on, stirring frequently, until the leeks are completely softened and starting to caramelize around the edges. Remove the thyme sprigs and discard them.
Step 3: Meanwhile, make the cheese sauce. Melt the 20g butter in a pan over medium heat, then stir in the plain flour. Cook for 1 minute to form a roux.
Step 4: Gradually pour in the milk in a steady stream, whisking constantly until the sauce thickens, about 6-8 minutes. When it reaches a boil, remove from heat.
Step 5: Stir in the grated nutmeg, Dijon mustard, gruyère, and cheddar. Season with salt and pepper, then fold in the softened leeks.
Step 6: Preheat the oven to 200°C (180°C fan)/gas mark 6. Lightly butter an ovenproof dish around 23cm wide.
Step 7: Mix the parmesan and fresh breadcrumbs with a generous pinch of black pepper. Pour the leek and cheese mixture into the prepared dish.
Step 8: Sprinkle the parmesan and breadcrumb topping evenly over the dish. Bake for 25-30 minutes until golden. If chilled, bake for an extra 5 minutes; if frozen, bake for an additional 10-15 minutes.

Tips & Variations

For extra depth, add a splash of white wine to the leek mixture while cooking.
Use a mix of your favorite cheeses to customize the flavor.
Vegetarian alternatives work well to keep this dish suitable for meat-free diets.
Serve with crusty bread or a fresh green salad for a complete meal.

Storage

Store leftovers covered in the refrigerator for up to two days. To reheat, warm in the oven at 180°C until heated through. This dish can also be frozen for up to one month; bake from frozen, adding extra time as noted above.

How to Serve

A round white ceramic baking dish contains a creamy layered casserole with two main visible layers: the bottom layer is a pale yellow creamy mixture with soft chunks, and the top layer is a thick, golden brown crumb crust that is crisp and uneven in texture, covering most of the dish except for a portion where the crust is scooped out, revealing the smooth creamy base underneath. In the background, a woman's hand is holding a white plate with food above the dish. The scene is set on a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use frozen leeks for this recipe?

Fresh leeks are best as they hold their texture and flavor, but you can use frozen leeks if necessary. Make sure to thaw and drain them well before cooking to avoid excess moisture.