1Heat oven to 350°F. Grease bottoms and sides of 3 (5x3-inch) loaf pans with shortening; lightly flour. In medium bowl, mix flour, baking powder and salt. In another medium bowl, mix sugar, oil and 2 tablespoons orange peel with wire whisk until blended. Stir in sour cream and eggs until well mixed. Add sugar mixture to flour mixture, gently stirring just until blended. Gently stir in 1/2 cup of the frozen cranberries.
2Divide batter evenly among pans. Sprinkle remaining 1/2 cup frozen cranberries evenly over loaves.
3Bake 45 to 50 minutes or until toothpick inserted in center comes out clean. Cool 10 minutes. Run knife around sides of pans to loosen loaves; remove from pans to cooling rack. Cool completely, about 1 hour.
4In small microwavable bowl, microwave frosting and 1 teaspoon orange peel uncovered on High 10 to 20 seconds; stir. Drizzle over loaves, allowing some to drizzle down sides.