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

In a large mixing bowl, beat the softened butter and granulated sugar together until light and fluffy.

Add the eggs, one at a time, mixing well after each addition. Stir in the vanilla extract.

In another bowl, whisk together the flour, baking powder, baking soda, and salt.

Gradually add the dry ingredients to the butter mixture, alternating with the buttermilk. Begin and end with the dry ingredients.

Gently fold in the crushed pineapple until evenly combined.

Divide the batter evenly between the two prepared cake pans.

Bake for 25 to 30 minutes, or until a toothpick inserted in the center comes out clean.

Allow the cakes to cool in the pans for 10 minutes before transferring them to wire racks to cool completely.

To make the frosting, combine the powdered sugar and lemon juice in a bowl and mix until smooth.

Once the cakes have cooled, spread the frosting generously between the layers and on top of the cake.

Optionally, sprinkle shredded coconut or crushed nuts on top for added texture and flavor.