Start this recipe the night before if possible. Slice the salmon fillet in half horizontally and squeeze over the orange juice. Cover and allow to infuse overnight if possible. When you are ready to prepare the salmon, heat the oil in a pan and fry the spring onions for 2 minutes to soften. Remove of the heat, stir in the spinach and wilt. Stir in chopped herbs, pine nuts and season with pepper only. Roll out the pastry into a large rectangle and brush all over with a little beaten egg. Place over one piece of the marinated salmon and cover with the olive pate. Pile on the spinach and spring onion filling and crumble over the feta cheese. Cover with the remaining piece of salmon and wrap up in the pastry. Seal the edges together firmly place onto a large baking tray. Brush all over again with egg and decorate with pastry leaves and sesame seeds. Use a sharp knife to make a few holes in the top to allow steam to come out during cooking. Bake in the oven at 200`c and cook for 30 minutes until golden brown. Allow to sit for 5 minutes before serving with roasted vegetables and potatoes.