Remove the legs from the goose by pulling away from the bone and cutting in half at the joint. Remove the wings and reserve for gravy.
Use a sharp knife to cut any fat and skin from the back of the goose. Place this fat in a tight-fitting oven tray with the goose legs, plus the garlic, peppercorns, orange rind, cloves, bay leaves, and cinnamon stick.
If the goose has giblets, reserve the liver and use for making stuffing. The rest can be used in the gravy, but beware the heart may make it a little too bitter.
If the neck is still attached, cut it off as close to the main body as possible. Using a heavy knife, remove the backbone from the goose, so you’re left with just the breasts on the bone (like a turkey crown).
Chop the backbone into smaller pieces and reserve for the gravy, and place any excess fat into the tray with the goose legs.
Place the legs in the oven and cook for 2 ½ - 3 hours, basting every so often until the meat is soft and just coming away from the bone. Once cooked, drain off the fat and reserve for roast potatoes or for another recipe. (The legs can also be cooked in advance and stored in their fat, in the fridge, then reheated for 25-30 minutes before serving.)
Season the goose breasts and place in a cold, oven-proof frying pan, skin-side down. Cook on a low heat for 5-10 minutes, until most of the fat renders out (reserve this for roast potatoes or another recipe).
Increase the heat to medium-high and continue to cook until the skin starts to colour and become golden. Gently turn over and cook for another few minutes before transferring to the oven and turning the heat up to 200C/Gas 6. Cook for 25-30 minutes, or until the breasts are perfectly pink.
Remove the pan from the oven and allow the breasts to rest for at least 20 minutes.
Thinly slice the breasts and roughly carve the legs, then serve with gravy and your favourite trimmings.