Chop orange, with skin, into 1/4-in. pieces. Set aside. Combine sugar and 2 Tbsp of the water in a large, heavy saucepan. Cook over medium heat, stirring until the mixture comes to a boil.
Continue cooking, without stirring, just until mixture turns golden brown. Stir in orange pieces, ginger, cinnamon stick and vanilla bean, if using. Cook, stirring, for 2 minutes.
Stir in cranberries, raisins and remaining 1/4 cup water. Cook over medium heat, stirring, for 5 to 8 minutes, or until half of the cranberries pop open.
Remove the pan from heat, stir in vanilla extract at this point, if using, and set aside to cool. Remove cinnamon stick and vanilla bean. Refrigerated in tightly closed jars, this relish keeps for 3 months.
Servings: 16