Combine the salt, black pepper, dried thyme, dried rosemary, paprika, garlic powder, onion powder, chicken bouillon and red pepper flakes in a bowl.
Unwrap your turkey and remove the giblets. Rinse it and pat it dry with paper towels. You want a dry turkey to ensure the brine sticks. Place the turkey on a clean, large baking sheet, board or tray.
Coat the whole turkey with the unsalted butter as this will help the seasonings and spices stick.
Sprinkle the dry brine mixture generously all over the turkey, making sure to get into all the nooks and crannies. Be thorough – you want that flavor everywhere! Don't forget to sprinkle some inside the turkey cavity as well.
Place the dry-brined turkey in a large bowl or reusable plastic bag. Now, the hard part - patience! Place the turkey in the refrigerator and let it chill for at least 24 hours (and up to 48 hours). This time allows the salt to work its magic, breaking down muscle proteins and making the meat juicy and tender.
When you're ready to roast, preheat your oven to 325°F (160°C). While the oven is warming up, take the turkey out of the fridge and let it come to room temperature for about an hour. This will ensure even cooking.
Stuff the turkey with chunks of onions, garlic, lemon wedges, spring onions, fresh rosemary and thyme.
Lay the turkey on a bed of cut-up potatoes, apple slices, more lemon wedges, white onion slices and spring onions.
Roast your turkey according to the weight – typically, it's about 13-15 minutes per pound. I roasted mine for approximately 4 hours.
Baste your turkey with some melted butter or turkey stock every 30 minutes to help it retain moisture and flavor.
Once your turkey reaches an internal temperature of 165°F (74°C), take it out of the oven, remove the foil and let it continue roasting for another 15 minutes for that gorgeous, golden-brown skin.
Take out the turkey and let it rest for about 30 minutes before serving This allows the juices to redistribute, ensuring a moist turkey. Now, it's time to carve and serve your masterpiece!