Weigh your turkey to calculate your cooking time - it needs approximately 18 - 20 minutes per 450g (lb).
We also suggest you sit it at room temperature for 20 minutes before cooking - this makes it easier to unwrap.
Once it's cooked, rest it for 30 minutes to one hour, to make it even more juicy. Add all these times together and work backwards from when you want to serve up, to see when to switch your oven on.
When you're ready to go, preheat the oven to 170°C / Fan 160°C / Gas 4, and place an oven shelf in the bottom third.
Remove your turkey from the freezer and sit in its packaging for 20 minutes at room temperature.
Unwrap your turkey and place it on top of a roasting rack inside a roasting tray. Drizzle with olive oil and season with salt and pepper.
Cook for 2½ hours, trying not to open the oven door or let out too much heat. After this time the turkey should be starting to turn golden.
Carefully take your turkey out of the oven, closing the door to retain the heat, and do your first temperature check.
Insert the temperature probe into the meatiest part of the breast, leaving it in place for at least 10 seconds to get an accurate reading.
If it reads below 74°C (it almost certainly will at this stage), it needs further cooking.
Tilt the turkey to pour any cooking juices into the roasting tray, and add about three glasses of liquid to the tray - white wine, chicken stock or water, according to taste.
Drizzle with a little more olive oil and return to the oven.
Repeat the temperature test after a further 45 minutes, and every 15 - 30 minutes after that - if it's close to 74°C, check it sooner.
Remember, all ovens vary! If the turkey is getting too brown, cover loosely with tinfoil.
For the final temperature test, check a few places on the breast, including close to, but not touching, the bone. Also check the thickest part of the thigh.
When each point reaches 74°C, remove the turkey from the oven, tip out any more juices to make your gravy, cover the turkey loosely with tinfoil and leave to rest in a warm place for 30 minutes to an hour before carving.
Use this time to complete your veg and gravy.
Pour yourself a glass of something tasty, serve up, and enjoy!