In a large bowl, combine the yellow cake mix, eggs, butter, flour, vegetable oil, and drained mandarin oranges.
Pour the cake batter into a 9x13-inch baking pan, and bake for about 20 to 25 minutes. The cake may not appear done but should be brown on top. Let cool, and cover with frosting.
To make the frosting: Thoroughly combine the pineapple, instant pudding, and powdered sugar, and set aside until it begins to thicken. Mix in the whipped topping and coconut. Frosting must be refrigerated.
Recipe Tips
This cake actually tastes better the day after baking, as the flavors have time to meld. For best results, make it a day in advance and keep refrigerated. When transporting to potlucks or picnics, keep chilled as long as possible, as the frosting can soften in high heat.