500g shallots, peeled and finely sliced (or use onions)
5 sage leaves, chopped
50g softened butter
4-6kg turkey, untrussed
400ml red wine
Heat 1 tbsp oil in a frying pan and gently cook the shallots with 1/2 tsp salt for about 20 minutes, stirring often. When they are soft, the colour of dark runny honey, stir in the sage and lots of black pepper. Leave to cool, then mix with the butter. Now for the squelchy bit. Ease your fingers under the turkey skin from the neck end, loosening it over the breast and thighs. Spread the shallot butter under the skin. Pat the skin back, then sprinkle the bird generously with sea salt. (You can do this a day in advance; chill until you need it, but take it out of the fridge a couple of hours before you cook it).
Heat the oven to 180C/fan 160C/gas 4. Put the turkey in a roasting tin and roast for about 22 minutes per kilo. For the last 45 minutes, whack the heat up to 200C/fan 180C/gas 6. Test by pushing a skewer into the thick part of the thigh: the juices should run clear. (If they’re a bit pink, give the bird 15 more minutes and test again.) Put the turkey on a serving dish, cover with foil, and rest for 20 minutes or up to an hour.
Meanwhile, make the gravy. Spoon as much fat as possible off the roasting tin juices. Put the roasting tin over the hob and splash in the wine. Stir and scrape the bottom of the pan with a wooden spoon while the wine bubbles up. Simmer for a couple of minutes, season. Sieve into a gravy jug or bowl. Serve with the turkey.