Follow pastry preparation instructions. Preheat oven to 220°C (200°C for fan assisted ovens) Gas M7.
Sauté the onion and garlic in oil for 5 minutes then add the courgette and pepper. Cook for a further 5 - 7 minutes then allow to cool.
Unroll the pastry sheet and cut into 4 rectangles. Crumble the feta cheese into the cooled vegetables, add the tomatoes and season to taste.
Divide the mixture on one half of the pastry, putting it just off centre of the length and leaving a border around filling of approx. 1 cm.
Brush pastry edges lightly with beaten egg and fold pastry over the filling pressing around the edges firmly to seal. Trim the sealed sides with a sharp knife, make a slit on the top and knock up edges to seal, then brush with beaten egg to glaze and sprinkle with poppy seeds.
Bake for 15 minutes until pastry risen and golden. Serve hot.