Name: Potato slab pie with salsa verde
Ingredients: 640g ready-rolled all-butter puff pastry rectangles (2 packs); 200g gruyère, roughly grated; 200g greek feta, roughly crumbled; 75g pitted green olives, roughly chopped; 12 spring onions, trimmed and finely sliced (100g); 30g parsley, finely chopped; 15g mint leaves, finely chopped; 4 large king edward potatoes, peeled, washed and very thinly sliced on a mandolin or by hand (540g); 4 large eggs plus 1 large yolk; 200ml double cream; 100g crème fraîche; 1 1⁄2 tbsp sesame seeds; salt and black pepper; 10g picked mint leaves; 15g picked basil leaves; 10g picked parsley leaves; 40g pitted green olives, roughly torn in half; 2 garlic cloves, peeled and roughly chopped; 15g anchovies packed in olive oil, drained; 2 tbsp apple cider vinegar; 60ml olive oil, plus extra for greasing

Baking Weekend project

Serves 8

Prep 35 min

Cook 1 hr 20 min

Think potato dauphinoise meets quiche, wrapped up in pastry. When asked why she created this pie, Verena responded, ‘I like pastry, I like potatoes and I like cheese, need I say more?’ That answers that, then. This rich and creamy pie is the perfect portable picnic food. It is quite generous, but rest assured that leftovers keep well in the fridge for up to 2 days. Just bring it back up to room temperature before eating, or heat in the oven if you prefer it warm.

Ingredients

640g	ready-rolled all-butter puff pastry rectangles (2 packs)
200g	gruyère, roughly grated
200g	greek feta, roughly crumbled
75g	pitted green olives, roughly chopped
12	spring onions, trimmed and finely sliced (100g)
30g	parsley, finely chopped
15g	mint leaves, finely chopped
4	large king edward potatoes, peeled, washed and very thinly sliced on a mandolin or by hand (540g)
4	large eggs plus 1 large yolk
200ml	double cream
100g	crème fraîche
1 1⁄2 tbsp	sesame seeds
	salt and black pepper
SALSA VERDE
10g	picked mint leaves
15g	picked basil leaves
10g	picked parsley leaves
40g	pitted green olives, roughly torn in half
2	garlic cloves, peeled and roughly chopped
15g	anchovies packed in olive oil, drained
2 tbsp	apple cider vinegar
60ml	olive oil, plus extra for greasing

Method

Preheat the oven to 180°C fan and place a large baking tray inside to heat up.
Grease a 32cm x 22cm x 3cm Swiss roll tin. Line with a piece of baking parchment large enough to cover the base and rise about 4cm up and over the sides (this will help you lift out the pie later).
Take one of the puff pastry sheets and roll it out to form a 38cm x 28cm rectangle. Transfer it to the prepared tin, making sure to push it inside the corners and up the sides. Refrigerate while you prepare the filling.
In a large mixing bowl, combine both the cheeses, the olives, spring onions, herbs, potatoes, 3⁄4 teaspoon of salt and a generous grind of pepper. Try to separate the potato slices as much as possible so they’re all evenly distributed.
Transfer the potato mixture into the pastry-lined tin, filling the corners and pressing down on the mixture so that it is tightly packed. It will seem like too much but it will cook down in the oven.
In a medium jug or bowl, whisk three of the eggs, the extra yolk, double cream and crème fraîche. Pour this evenly over the filling.
Unroll the second piece of puff pastry and lay it on top of the potatoes, tucking it between the potatoes and the pastry sides. Lightly whisk the remaining egg and brush this over the pastry. Then, with a slight lifting and pulling motion, fold the pastry sides over the edges of the top layer and press down gently to seal. Brush the edges with egg wash and sprinkle over the sesame seeds. Using a sharp knife, make seven diagonal scores along the length of the top of the pie, each around 5cm long.
Carefully, place the pie tin on top of the hot baking tray in the oven and bake for 30 minutes. Rotate the tin and bake for another 30 minutes until golden and cooked through. If the top of the pie gets too dark too early, turn the heat down to 170°C fan. Remove from the oven and leave to cool in the tin and on a wire rack for about 1 hour.
Use the paper overhang to lift and slide the pie out of the tin. Set the tin aside and place the pie back on to the wire rack to cool completely, about 11⁄2 hours. Cut into 20 squares.
While the pie is cooling, make the salsa verde. Put all the herbs, the olives, garlic, anchovies, vinegar, half the oil and plenty of pepper into a food processor and pulse a few times, scraping down the sides of the bowl as necessary, until you have a coarse paste. Stir in the remaining 2 tablespoons of oil, then transfer to a serving bowl to eat alongside the pie.