In a large bowl, mix the softened butter and sugar well with a hand mixer.

Add the flour, baking soda, and baking powder to the butter-sugar mixture and mix well.

Add milk, oil, and pineapple chunks.

Add 1/2 cup of shredded and toasted coconut.

If desired, add a teaspoon of coconut rum and mix evenly.

Preheat oven to 325 degrees F for 10 minutes.

Grease two 8-inch pans and pour the cake batter into them.

Bake in the preheated oven for 25 minutes or more, until a toothpick inserted in the middle comes out clean.

Take the pans out and cool on a wire rack.

For the frosting, beat the butter until it becomes light in a blender.

Add sugar and coconut milk to the butter and mix well to achieve a creamy texture.

Take the cakes out of the pans.

Place one cake on a plate and apply frosting all over it.

Arrange four pineapple slices and toasted coconut on the frosting.

Carefully place the other cake on top.

Apply frosting again over the second cake, covering both completely.

Spread toasted coconut all over the cake carefully.

Arrange the remaining pineapple slices as desired.

Refrigerate for at least 2 to 3 hours before serving.

Serve the Pina Colada Cake with Samosa, Cold Coffee Smoothie, or other snacks.