8 asparagus spears - woody ends trimmed, and sliced into 5cm lengths
100g fresh or frozen peas
4 spring onions - thinly sliced
200ml double cream or soya cream
40g bunch fresh parsley
Zest of 1 lemon
2 tbsp pine nuts
½ tsp salt
½ tsp vegetable stock powder
A little milk or soya milk to glaze
Preheat the oven to Preheat the oven to 180°C / 350°F / Gas Mark 4.
Unroll the pastry and roll it a little more thinly to create a slightly longer, thinner rectangle, then cut it into two equal sized rectangles. Line a large baking tray with greaseproof paper or baking parchment, and place one of the rectangles on the tray, leaving the other aside for now.
Bring a large saucepan of water to the boil, then add the sliced potatoes. After they have been cooking for 4 minutes, add the broccoli and leek. After a further 4 minutes, add the asparagus and peas, then after 2 minutes, remove from the heat, drain then return to the saucepan, add the spring onions, and set aside to cool.
In a hand blender or food processor, blitz the cream, parsley, lemon zest, pine nuts, salt and stock powder together into a sauce. Pour the sauce over the vegetables, and stir to combine until all the vegetables are evenly coated.
When they are cool, carefully pile the vegetables into the centre of the pastry, leaving at least 2cm border around the edges. If there is some creamy sauce in the bottom of the saucepan, pour this into the centre of the pile of vegetables so that it doesn't spread to the edges of the pastry.
Brush a little water around the edges of the pastry, then place the second rectangle of pastry over the top. Press the edges together firmly with your finger to seal together, then use a fork to crimp the edges to make it look pretty. Use the back of the blade of a sharp knife to gently score lines in the top of the pastry, then brush the whole lot with milk or soya milk.
Bake in the oven for 25-30 minutes until golden brown and the pastry is cooked throughout.