Preheat the oven to 210°c (190 fan) and line two baking sheets with baking paper.
In a large bowl mix together the sausage meat, apple sauce, and dry stuffing mix.
Lay your ready-rolled puff pastry sheet onto a board and cut it into 3 equal horizontal slices with a sharp knife.
Equally distribute the sausagemeat into the middle of each horizontal slice of pastry, leaving a gap on the top and bottom edges.
Brush the bottom edges with egg then fold the tops over to meet the bottoms. Use a fork to press down the pastry and secure the sausage meat inside.
Cut each long roll into 10-12 equal slices, depending on how small you want your sausage rolls to be. Place on a lined baking sheet.
Glaze with an egg and bake for 20 minutes.