enclose the bulb and roast on a baking tray for 25-30 mins, or until soft when pressed. Leave to cool for a few minutes before removing the foil and papery skin from the bulb. Strip the leaves from the remaining thyme sprigs (reserving the stems) and tip into a bowl. Squeeze in the roasted garlic cloves and add the butter, parsley, lemon zest and juice. Season well, then mash everything together to combine. Will keep chilled for up to three days or frozen for a month.
If you have time, season the turkey 24 hrs before roasting (this helps create crispy skin). Scatter the reserved thyme stems and the juiced lemon half into the base of a roasting tin. Place the crown on top, cavity-side down, then season generously all over. Cover and chill for up to 24 hrs.
Remove the turkey and garlic butter from the fridge 1-2 hrs before roasting to come to room temperature. Heat the oven to 200C/180C fan/gas 6. Use your fingers or a spoon to gently push under the skin of the
