Heat oven to 350°F (325°F for dark or nonstick pan). Spray bottom only of 13x9-inch pan with baking spray with flour.
2 In large bowl, beat cake mix, eggs, 1 cup water and the oil with electric mixer on low speed 30 seconds. Beat on medium speed 2 minutes, scraping bowl occasionally. Pour batter into pan.
3 Bake 28 to 33 minutes or until toothpick inserted near center comes out clean. Cool completely in pan on cooling rack, about 1 hour.
4 Poke cake all over with fork or wooden skewer. In medium bowl, pour boiling water on 1 box orange gelatin; stir until gelatin is dissolved. Stir in cold water. Pour gelatin over cake. Run knife around edges of pan to loosen cake. Refrigerate 2 hours.
5 In large bowl, stir together pudding mix, 1 box orange gelatin, the milk and orange juice until blended. Fold in 1 container whipped topping. Spread over cake. Cut into squares. Garnish with additional whipped topping and orange peel. Store covered in refrigerator.
Reduce the calories by substituting sugar-free gelatin and pudding, low-fat milk and reduced-fat whipped topping.
After pouring the gelatin over the cake, be sure to run a knife around the edges to loosen the cake from the pan.