Easy leek and gruyère tart
Rustically rough and loaded with gentle leeks and smooth cheese, this tart is a snap to get together.
The combination of cheese and onion is as classic as it is irresistible. It’s the heart of the ploughman’s lunch – think vinegary, crunchy pickled onions and sharp cheddar cheese – all the way through to gentler extravaganzas like my leek and brie risotto. Here the duo are paired again, both in their mildest forms, in a rustically rough puff pastry casing.
This takes about 30 minutes from first move to table, and your attention isn’t required for most of that time, so it’s easy to get together for lunch or a light dinner.
I start with a sheet of good puff pastry that’s about 30cm (12 inches) square, thawed in the fridge overnight (or for 1 hour out of the fridge if you’re pushed for time). Use something of similar size and things will work out fine – this is a forgiving recipe.
For the cheese, I generally use gruyère as it’s something of a permanent resident in my fridge. Other melting cheeses such as gouda, provolone, Emmental or Jarlsberg are all great substitutes – anything mild, melty and with a slightly nutty edge that won’t overwhelm the delicate flavour of the leeks.
Alongside you need nothing more than a few simply dressed green leaves; a lemony dressing with a spoonful of Dijon mustard whisked in would be perfect.
Easy leek and gruyère tart
1 sheet puff pastry
100g (4 oz) gruyère cheese, coarsely grated
1 teaspoon thyme leaves
2 tablespoons milk
sea salt flakes
freshly ground black pepper
Set your oven to 200°C (400°F) and line a baking sheet with baking paper.
Lay the puff pastry on the paper and fold each side in by 2cm (a bit less than an inch). Press the corner folds together lightly and prick the flat area inside the frame all over with a fork.
Trim the leeks to produce a couple of logs using the white and pale green parts. Cut them in half lengthways, then continue to cut them lengthways until you have lots of long, thin pieces, about 5mm (¼ inch) wide.
Fill the tart with half the cheese and lay the strips of leek across from end to end. Scatter over half the thyme leaves.
In a small bowl, mix together the eggs and milk, seasoning with salt and a generous amount of pepper. Brush the edges of the tart with a little of this mixture, then set it aside.
Bake the tart for 15 minutes – it should be rising nicely and the leeks will have softened up. Pour over the egg and milk mixture and top with the rest of the cheese and thyme leaves. Return to the oven for another 10 minutes or until the pastry is golden brown and the eggy filling has set.
Let the cooked tart rest for 10 minutes before slicing and serving.