An easy recipe for an orange creamsicle cake is Duncan Hines' cake using prepared cake mix, instant pudding mix, instant Jell-O mix and Cool Whip. The cake and the frosting both have an orange creamsicle flavor and the cake takes about 30 minutes to prepare.
To make Duncan Hines' Orange Creamsicle Cake, combine a box of Duncan Hines Orange Supreme Cake mix, a 3 1/2-ounce box instant vanilla pudding mix, 4 eggs, 1/3 cup oil and 1 cup water using an electric mixer on medium speed. Pour the cake batter into prepared cake pans and bake according to the instructions on the cake mix box.
Before the cake cools, combine a 3-ounce box orange Jell-O and 1 cup boiling water until the Jell-O is dissolved. Use a fork or a straw to put holes in the cake and pour the hot Jell-O over the still warm cake. Allow the cake to cool.
Meanwhile, make the frosting by mixing together a 3 1/2-ounce box of instant vanilla pudding and 1 cup milk. Add in 1 teaspoon vanilla and orange extracts, and then carefully stir in an 8-ounce container of thawed Cool Whip. Spread frosting between the cooled cake layers and on top of the cake. Place the cake in the refrigerator for at least two hours before serving.