Preheat the oven to 350°F. Spray three 8-inch cake pans with baking nonstick spray. Line the bottoms of the pan with 8-inch parchment paper circles. Spray again.
Pour the crushed pineapple into a colander. Use a rubber spatula to press juice out of the pineapple. There will be a lot of juice, do this as much as you can. Set aside.
2 cups Crushed pineapple
In a medium bowl, sift the flour. Add the baking soda, baking powder, and salt.
3 1/2 cups All-purpose flour, 2 tsp Baking soda, 1 tsp Baking powder, 1 tsp Salt
In a large bowl, mix the melted butter (make sure it is cooled!), oil, sugar, sour cream, vanilla, crushed pineapple, eggs, and buttermilk. Mix using a whisk.
1/2 cup Unsalted butter, 1/2 cup Oil, 1 1/2 cups White granulated sugar, 1/2 cup Sour cream, 1 tsp Pure vanilla extract, 2 cups Crushed pineapple, 4 Large eggs, 1/2 cup Buttermilk
Pour the dry ingredients into the wet ingredients. Whisk until just combined.
Pour the batter evenly between the three cake pans. Bake for 20-25 minutes until a toothpick inserted comes out clean.
Let the cakes sit in the hot pans for 10 minutes. Then, transfer to a cooling rack. Cool the cakes completely before decorating.