01 - Preheat oven to 350°F. Grease a 9x13-inch baking pan thoroughly.
02 - Combine yellow cake mix, eggs, crushed pineapple with juice, vegetable oil, and water in a large bowl. Beat until batter is smooth and well blended.
03 - Pour batter into prepared baking pan. Bake for 28-32 minutes until a toothpick inserted into the center comes out clean.
04 - Allow cake to cool for 10 minutes. Using the handle of a wooden spoon, poke holes throughout the cake at approximately 1-inch intervals.
05 - Whisk together sweetened condensed milk and coconut milk until fully combined. Drizzle evenly over the warm cake, allowing liquid to seep into the holes.
06 - Combine instant vanilla pudding mix, cold milk, and pineapple juice in a bowl. Whisk for 2 minutes until thickened. Spread pudding mixture evenly over the cake.
07 - Cover pan and refrigerate for at least 1 hour until completely chilled and set.
08 - Spread thawed whipped topping evenly over the chilled cake surface.
09 - Sprinkle toasted coconut over the top. Decorate with fresh pineapple chunks and maraschino cherries if desired. Slice and serve cold.