Line a 38 x 26cm baking tray with parchment paper. Lay the two sheets of puff pastry side by side, slightly overlapping. Trim any excess pastry around the edge of the tray.
Slice the leeks into 1cm rounds and give them a good rinse to remove any dirt.
In a large pan add one teaspoon of oil on medium heat, add the leeks and a quarter teaspoon of salt and cook for one minute, then add two tbsp of water and cover the pan with a tightly fi tted lid to trap the steam. Cook for 3-4 minutes until the leeks are softened.
For the tomato sauce, mix together the passata, three tablespoons of The Happy Pear Pesto and ½ teaspoon of salt.
Spread the sauce in an even layer over the puff pastry, leaving about 2.5cm from the edges for a big golden crust.
Scatter the cooked leeks over the sauce. Slice the vegan sausages and scatter over the sauce.
Brush the pastry edges with some non-dairy drink if you have it.
Bake in the oven for 10 minutes until the pastry is golden brown.
To serve, add the rocket and a few more dollops of pesto, slice and enjoy!