Preheat the oven to 180°C
Lightly sauté onion til softened and set aside to cool
In a large bowl, add all filling ingredients and mix well using your hands to squeeze the mixture together
Cut pastry in half on the long side
Place filling evenly onto the middle of the pastry and fold on side over, then brush the egg mix over the other edge and fold over to cover the filling
Cut into even size sausage rolls, and run a knife along the top of each roll - slicing two diagonal cuts
Brush with egg mix and bake for 40 minutes until meat and pastry are cooked through and golden brown
