Preheat the oven to 200°C / 180°C fan / gas mark 6. Line a large baking tray with baking parchment. Add the sheet of puff pastry to the tray. Trim a 2cm strip from each side of the pastry.
Brush the edge of the remaining sheet of pastry with egg wash, then add each strip back on top, along the edge, trimming if needed. Using the back of a fork, press into the strips of pastry around the edge and prick the sheet of pastry.
Mix the mascarpone and pesto and spread in an even layer over the base sheet of pastry. Toss the asparagus, courgette, dill, oil, salt and pepper together and scatter in an even layer over the mascarpone.
Brush the edge of the pastry with the remaining egg wash. Bake for 15–20 minutes until the pastry is golden brown.
Then add the salmon evenly as the final topping. Bake for another 5 min.
Serve with your favourite side salad.
... and receive a 15% welcome discount. Get exclusive insights, news, delicious recipes and most importantly - our exclusive offers!