In a small mixing bowl, combine powdered sugar and vanilla. Stir in 1 tablespoon milk (or orange juice). Stir in additional milk (or orange juice), 1 teaspoon at a time until icing is smooth and of drizzling consistency. Drizzle icing over cake, bread, or cookies. Chocolate Powdered Sugar Icing; Prepare icing as directed above, except add 2 tablespoons unsweetened cocoa powder to the powdered sugar. Liqueur Powdered Sugar Icing; Prepare icing as directed above, except substitute 1 tablespoon desired liqueur for the first 1 tablespoon milk or orange juice.