This is almost a potato gratin in a pie, with layers of gooey leek, potato slices and cheddar cheese. Take your time to create the layers, bake well and serve warm with a crisp salad.
Makes a 22cm pie for six people.
PASTRY
Toasted Walnut Short Pastry (see recipe below)
FILLING
4 medium waxy potatoes, peeled and thinly sliced
2 tbsp olive oil
1 tbsp butter
4 large leeks, cleaned, halved lengthways and chopped into large pieces
Salt and pepper, to taste
4 cloves garlic, peeled and finely chopped
350ml sour cream
2 large eggs, lightly beaten
2 tbsp wholegrain mustard
180g vintage cheddar, grated
1 bunch fresh chives, finely chopped
1 bunch flatleaf parsley, finely chopped
METHOD
Set oven to 190C. Make Toasted Walnut Short Pastry ahead and rest it as required. Then, on a lightly floured surface, roll out to approximately 3mm thick to line a 22cm spring-form cake tin (5.5cm deep). Lightly oil the tin, then line with pastry, trimming it 2cm from the top of the tin. Put in the refrigerator to chill.
Bring a medium saucepan of water to the boil, add sliced potatoes and cook for 3-4 minutes until beginning to soften. Drain well and set aside.
Heat oil and butter in a large saucepan on a medium-high heat. Add chopped leek, season with salt and pepper and cook for 2-3 minutes. Add garlic and cook for a further 3 minutes.
Remove pan from the heat and leave leeks and garlic to cool slightly (15 minutes).
In a large bowl mix sour cream, eggs, mustard, most of the cheddar (reserving about 4 tablespoons for the top), the chives, parsley and a good pinch of salt. Stir in the cooled leeks and garlic.
Remove the pastry-lined tin from the refrigerator. Cover the base with a single layer of well-drained potato, then spoon the creamy leek mixture over the potato, repeating the layering until both the potato and leek mixture are used up, with the last layer being the potato.
Place the pie in the oven and bake for 40-45 minutes. Scatter the remaining cheddar on the top and return it to the oven for 5-10 minutes until it has turned golden in colour.
The filling should still be gooey, but hold its shape when cut into wedges.
TOASTED WALNUT SHORT PASTRY
50g walnuts, shelled
160g standard plain flour
1 tbsp caster sugar
120g butter
good pinch of salt
50ml cold water
Set oven to 170C.
Spread walnuts on an oven tray and lightly toast in the oven until light amber in colour. Finely chop walnuts (1-2mm in size) and set aside.
Place flour, sugar, toasted walnuts, butter and salt in a large mixing bowl. Using your fingertips, gently rub ingredients together until they resemble rough breadcrumbs. Do not over-mix otherwise butter will begin to melt from the heat of your fingers.
Add water and mix until a dough is formed. Cover with plastic wrap and refrigerate for 30 minutes or overnight.
Gently rework pastry before using, taking care to ensure it remains cold and firm.
On a lightly floured surface, roll out pastry as stated in your recipe.