01 -
Preheat oven to 350°F (175°C) and grease a 9x13-inch baking dish.
02 -
In a large mixing bowl, combine the cake mix, pistachio pudding mix, vegetable oil, eggs, and crushed pineapple with its juices. Beat until well combined.
03 -
Transfer the batter to the prepared baking dish and bake for 30-35 minutes or until a toothpick inserted into the center comes out clean. Allow the cake to cool completely.
04 -
In another bowl, mix the pistachio pudding mix and whole milk until the mixture thickens. Fold in the thawed cool whip until fully incorporated.
05 -
Spread the frosting evenly over the cooled cake. Chill in the refrigerator for 2 hours before serving.
06 -
Optionally, sprinkle chopped pistachios on top. Slice and serve.