Preheat the oven to 220 degrees.

Fry the bacon lardons over a medium heat until golden. Finely slice the leeks and add them to the fryng pan; fry for another 3-4 minutes.

Unroll the pastry, lay on a baking tray and score all the way around the edge, 1 inch from the sides (don’t cut all the way through). Beat the egg in a bowl and brush a little around the outside edges.

Spread the soft cheese evenly over the inside scored rectangle of the pastry. Grind some black pepper over the top, then evenly layer on the bacon and leek mix. Sprinkle over the walnuts, and dot the gorgonzola over.

Bake in the oven for 15-20 minutes, until the sides are golden and puffed up.