step 1: Preheat oven to 350°F (175°C). Grease and flour two 8-inch or 9-inch round cake pans, lining bottoms with parchment paper. Measure all ingredients and bring butter, cream cheese, and eggs to room temperature.

step 2: In a large bowl, whisk together the all-purpose flour, granulated sugar, baking powder, baking soda, and salt for 30 seconds to aerate and distribute.

step 3: In a stand mixer, cream the room temperature unsalted butter until light (2 minutes). Gradually add granulated sugar, beating on medium-high for 3-5 minutes until pale and fluffy.

step 4: Beat in room temperature large eggs, one at a time, mixing well after each addition and scraping down the bowl.

step 5: On low speed, alternately add dry ingredients (in thirds) and buttermilk (in halves) to the butter mixture, mixing just until no dry streaks remain. Do not overmix.

step 6: Gently fold in the undrained crushed pineapple and shredded coconut using a rubber spatula until evenly distributed.

step 7: Divide batter evenly between prepared pans. Bake for 28-35 minutes, or until a toothpick inserted into the center comes out clean with a few moist crumbs.

step 8: Cool cakes in pans on a wire rack for 10-15 minutes, then invert onto racks, remove pans/parchment, and cool completely for at least 2 hours.

step 9: In a clean mixer bowl, beat room temperature unsalted butter and cream cheese on medium speed for 3-4 minutes until smooth, light, and fluffy. Scrape bowl frequently.

step 10: On low speed, gradually add sifted powdered sugar (one cup at a time). Add vanilla extract, then beat on medium-high for 2-3 minutes until light and fluffy. Adjust consistency with heavy cream or more powdered sugar if needed.

step 11: Trim domed cake tops flat using a serrated knife or cake leveler for even layers.

step 12: Place one cooled cake layer on a serving plate. Apply a thin crumb coat of frosting to the top and sides, then chill for 15-20 minutes to set.

step 13: Once crumb coat is set, stack the second cake layer. Apply a generous amount of frosting to the top and sides, spreading evenly and smoothly.

step 14: Garnish by pressing toasted shredded coconut around the sides and/or sprinkling over the top. Optionally add toasted macadamia nuts or pecans.