Instructions: Preheat Oven: Preheat your oven to 350°F (175°C). Grease and flour a 9-inch round cake pan.
Prepare the Cake Batter: In a large bowl, combine flour, sugar, baking powder, baking soda, and salt.Add softened butter, eggs, vanilla extract, crushed pineapple, coconut milk, and rum (if using). Mix until well combined.
Bake the Cake: Place the cake pan in the preheated oven and bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean.
Prepare the Filling: In a mixing bowl, combine instant vanilla pudding mix and coconut milk. Whisk until smooth and thickened.
Assemble the Cake: Once the cake has cooled, carefully slice it in half horizontally to create two layers.Place one cake layer on a serving plate or cake stand.
Chill and Serve: Chill the assembled cake in the refrigerator for at least 1 hour before serving to allow the flavors to meld.