In 1-quart saucepan, heat 1 ounce chocolate and 2 tablespoons butter over low heat 2 to 3 minutes, stirring occasionally, until melted. Remove from heat. With wire whisk, beat in powdered sugar and 1 tablespoon of the orange juice. Beat in additional orange juice, 1 teaspoon at a time, until glaze is smooth and consistency of thick syrup. Drizzle glaze over cake, allowing some to run down side. Garnish with orange peel strips.