If duckling is frozen, defrost completely.
Rinse and dry inside and out.
Refrigerate giblets to cook later.
Stuff the duckling with 1 quartered orange or your favorite stuffing.
Lace or sew cavity closed and truss the bird.
Roast on a rack in a shallow roast pan 350F for 2 to 2 1/2 hours or until thigh meat is soft.
Pour off the drippings and fat as they collect in the pan during roasting.
Chill drippings in a glass measuring cup.
Meanwhile, heat the sugar and vinegar together in a small saucepan until the sugar dissolves and syrup turns a light golden brown color.
Cut 3 or 4 slices from an orange and drop slices individually into the syrup.