Preheat the oven to 200C/400F/Gas 6.
Place the pastry on a baking sheet and brush the edges with beaten egg.
Lay the basil leaves in the middle of the pastry, top with the salmon fillet, then the whole spring onion, drizzle with honey, season to taste with salt and freshly ground black pepper, then wrap the edges of the pastry over the salmon to make a parcel.
Brush with more beaten egg and bake in the oven for 12 minutes, or until puffed up and golden on top.
To serve, slice in half on the diagonal.