No need to preheat oven.
Heat oil in a frying pan and fry bacon until crisp and golden.
Lower the heat and add onion and garlic and cook until soft.
Add sage, remove from heat and allow to cool.
Add the walnuts, breadcrumbs and egg, mix well then stuff into the cavity of the chicken.
Place chicken into the roasting bag with the potatoes, carrots and butternut and season with dry KNORR mixture. Close bag at end with blue tie supplied.
Very gently massage KNORR mixture into the chicken on a stable surface. Ensure dry mixture is spread evenly.
Place bag sideways in a cool oven dish, ensuring pieces are evenly spaced.
Bake at 180°C for 70 minutes on the lowest shelf in the oven. Ensure that the grill is off at all times. Keep enough room for the bag to expand (bag must not touch the sides of the oven).
For a crispier skin, open the bag 15 minutes before the end of cooking.