A chilled orange poke cake with orange gelatin baked into the batter, a sweetened condensed milk and mandarin orange soak, and a creamy vanilla pudding topping. Make it the day before - it only gets better.
Preheat your oven to 350 degrees F. Grease a 9-inch x 13-inch baking dish with non-stick cooking spray. Set aside.
Add 1 box white cake mix, along with the ingredients listed on the package, and 3 ounces orange gelatin mix to a large mixing bowl. Whisk until evenly combined.
Pour the cake batter into the prepared pan. Bake according to the package directions.
While the cake bakes, whisk together 14 ounces sweetened condensed milk and the reserved ¾ cup mandarin orange juice from the canned oranges.
Once the cake is done, remove it from the oven and let rest for 5 minutes. Then use a fork or chopstick to poke holes all over the top. Pour the soak mixture evenly over the cake. Let sit until the cake cools completely, about 1-2 hours.
When the cake has cooled, whisk together 3.4 ounces instant vanilla pudding mix and 1 cup whole milk in a medium mixing bowl for 1 minute, until thickened. Fold in 8 ounces Cool Whip until no longer streaky. Add 15 ounces canned mandarin oranges and stir them in, breaking up the segments a bit.
Spread the topping over the top of the cake in an even layer. Cover the baking dish with plastic wrap and refrigerate for 4 hours to overnight to set.
Remove the cake from the fridge and cut it into 12 slices. Garnish each slice with a mandarin orange and a mint leaf, if desired. Serve immediately.
Notes
You can use vanilla or French vanilla-flavored instant pudding mix. French vanilla will give the topping a richer, custard-like flavor. White chocolate and cheesecake flavors will work too.
If you can't find white cake mix, vanilla or yellow cake mix will work too. For extra orange flavor, use orange cake mix.
You can use fresh-squeezed orange juice in place of the mandarin orange juice.
For the most even soak, poke holes across the entire cake and pour the condensed milk mixture slowly over the surface rather than concentrating it in one area.
Store leftovers in the fridge in an airtight container for up to 3 days.