01 - Preheat oven to 350°F. Grease a 9x13-inch baking pan with cooking spray or butter.
02 - Combine yellow cake mix, eggs, crushed pineapple with juice, vegetable oil, and water in a large bowl. Beat with electric mixer on medium speed until smooth, approximately 2 minutes.
03 - Pour batter into prepared baking pan. Bake for 28-32 minutes until a toothpick inserted in the center comes out clean. Remove from oven and let cool for 10 minutes.
04 - Using the handle of a wooden spoon, poke holes evenly across the entire cake surface, spacing approximately 1 inch apart.
05 - Whisk together sweetened condensed milk and coconut milk in a medium bowl until thoroughly combined, about 1 minute.
06 - Slowly pour the milk mixture evenly over the warm cake, ensuring liquid fills the poke holes. Allow to absorb for 5 minutes.
07 - Whisk instant vanilla pudding mix, cold milk, and pineapple juice in a separate bowl until thickened, approximately 2 minutes. Spread evenly over the cake.
08 - Cover pan with plastic wrap and refrigerate for at least 1 hour until completely set and chilled.
09 - Spread whipped topping evenly over the chilled cake surface using an offset spatula.
10 - Sprinkle toasted coconut over the top. Decorate with fresh pineapple chunks and maraschino cherries if desired. Slice into 12 servings and serve cold.