Name: Easy cheesy leeks
Prep time: 35 min
Cook time: 1 h
Total time: 1 h 35 min
Yield: 8
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

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

For the cheese sauce

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

Method

step 1
Set a large, deep pan over a medium-low heat and warm the oil and butter. When foaming, add the leeks, garlic and thyme along with a generous pinch of salt.
step 2
Cook for 25-30 mins with the lid on, stirring frequently, until the leeks are completely softened and beginning to caramelise around the edges. Remove the thyme sprigs and discard.
step 3
Meanwhile, make the sauce. Melt the butter in a pan over a medium heat, then stir in the flour. Cook for 1 min. Pour in the milk in a steady stream, whisking constantly, until you have a thick sauce, about 6-8 mins. When it comes to the boil, remove from the heat and stir in the nutmeg, mustard and both cheeses. Season, then stir in the leeks.
step 4
Heat the oven to 200C/180C fan/gas 6. Lightly butter an ovenproof dish around 23cm wide. Mix the parmesan and breadcrumbs with a generous pinch of black pepper.
step 5
Pour the leek mix into the dish. Will keep chilled for up to two days and frozen for up a month. Sprinkle with the parmesan crumbs and bake for 25-30 mins (5 mins longer if chilled, and an extra 10-15 mins from frozen), until golden.