To prepare a roast goose, cover the goose in water and 1/4 cup of sea salt. Refrigerate overnight before draining the water and removing any innards that were included. Preheat the oven to 450 degrees Fahrenheit. Rub the inside of the goose with lemon juice, and stuff it with a chopped apple, a quartered potato, 1 cup of chopped celery and a sliced orange. Reduce the oven to 350 degrees Fahrenheit, and roast the goose for 20 minutes per pound.
Roast the goose at 350 F for 20 minutes per pound, and baste it every 30 minutes with a basting syrup. Prepare a basting syrup by combining 1/3 cup of corn syrup, 1/3 cup of cane syrup, 1/3 cup of melted butter, 1/4 cup of brown sugar and 2 tablespoons of brandy in a mixing bowl.
Serve the goose with a Cumberland sauce made by combining 1 1/2 cups of beef stock, 3/4 cup of port wine, 3/4 cup of red wine vinegar, 3 peeled and chopped shallots, and 1 tablespoon of black peppercorns in a saucepan. Bring to a boil, and cook for 25 minutes or until reduced by 2/3. Strain and refrigerate the sauce. Serve the Cumberland sauce cold with the roast goose.