Preheat oven to 350°F (175°C). Grease and flour two 9-inch round cake pans or line with parchment.

In a bowl, whisk flour, baking powder, baking soda, and salt. Set aside.

Cream butter and sugar together until light and fluffy, about 3-4 minutes.

Add eggs one at a time, beating well after each. Stir in vanilla.

Fold in crushed pineapple. Alternate adding dry ingredients and buttermilk, starting and ending with dry.

Divide batter into pans. Tap to release air bubbles. Bake 35-40 minutes or until a toothpick comes out clean.

Cool in pans for 10 minutes, then transfer to wire rack to cool completely.

For frosting, beat cream cheese and butter until smooth. Gradually add powdered sugar, then pineapple juice and vanilla. Beat until fluffy.

Frost one cake layer, top with second layer, and frost entire cake. Decorate with pineapple chunks, coconut flakes, and mint if desired.

Chill for 30 minutes before slicing and serving.