To make the Sausage meat stuffing, in a bowl, combine the sausage meat, breadcrumbs, herbs, onion, garlic, mature cheddar. Check the seasoning and set aside until needed.
Place a piece of parchment paper on a work surface. Line the pieces of streaky bacon side by sides so it should fit to cover the turkey breast and add a second layer of parchment of paper. Using a rolling pin, roll the bacon to flatten and spread them until it reach about a double in length.
Add the butterflied turkey breast over and add the stuffing.
Roll the bacon and turkey piece up to form a long roll. Tie every 2 inches with kitchen twine. Drizzle with remaining 2 tablespoons olive oil. Season with salt and pepper. Tuck rosemary branches along the top of the roll under the twine.
Weigh the joint and calculate the cooking time, allowing 15 minutes per 450g plus 20 minutes.
Preheat the oven to 200˚C.
Place the turkey joint into a roasting tin with a carrot, garlic and sliced onion as a raft.
Spread some softened butter over the bacon on the turkey and season well with salt and pepper.
Place the turkey into the oven and roast it for about 1hour 40 minutes or until the juices run clear.
Lift the turkey joint onto a board, cover with foil like a tent and leave it to rest for 10 minutes, before carving and serving! In the meantime prepare the gravy!