Before you start, I recommend taking the turkey out of the fridge at Least 2 hours before you cook it.
Step 1 – The stuffing
Melt 20g of the butter in a frying pan over medium-high heat until foaming. Add bacon, onion and garlic and cook, stirring, for 5 minutes or until onion softens. Transfer to a heatproof bowl. Add the breadcrumbs, walnuts, sage and egg and stir until well combined. Season with salt and pepper.
Preheat oven to 180°C. Rinse the turkey inside and out under cold running water. Pat dry with paper towel. I prefer to place the breadcrumb mixture in to the neck part of the turkey, under the skin, rather than the cavity. This allows a better airflow while the turkey is cooking.
In the cavity you can place a small bunch of thyme or rosemary, or a mixture of both, this will give a lovely aroma and flavour. Tie the legs together (optional since the stuffing will be under the skin of the neck) with unwaxed white kitchen string. Tuck the wings under. Place turkey, breast-side up, in a roasting pan. Brush the remaining butter over the turkey, season with salt pepper and grate 1/2 nut meg over the turkey for a Christmassy flavour, and cover with foil. Roast in oven, basting every 30 minutes, for 3 1/2 hours or until juices run clear when thigh is pierced with a skewer. Take the foil cover off for the last 30 minutes of cooking. Transfer turkey to a platter. Remove string. Cover with foil and set aside for at least 30 minutes to rest.
Step 3 – The gravy
Strain the pan juices into a heatproof jug. Melt the butter (50g) in the roasting pan over medium heat until foaming. Add the flour and cook, stirring, for 2 minutes or until mixture bubbles. Gradually add the pan juices, wine and stock and cook, scraping the pan with a flat-edged wooden spoon to dislodge any bits that have cooked onto the base, for 5-6 minutes or until gravy boils and thickens. Taste and season with salt and pepper. Strain into a heatproof serving jug.
Place the turkey on a large serving platter and serve with gravy.