01 - Preheat oven to 350°F (175°C). Line a standard muffin tin with 12 paper cupcake liners.
02 - In a medium bowl, whisk together the all-purpose flour, baking powder, and salt until evenly combined.
03 - In a large mixing bowl, use an electric mixer to cream softened butter and granulated sugar until light and fluffy. Add eggs one at a time, blending thoroughly after each addition.
04 - Stir in the crushed pineapple, reserved pineapple juice, milk, and vanilla extract, mixing just until incorporated.
05 - Add the flour mixture to the wet ingredients, blending on low speed until just combined. Avoid overmixing the batter.
06 - Divide the batter evenly among the prepared liners. Bake for 16 to 18 minutes, or until a toothpick inserted in the center comes out clean.
07 - Let the cupcakes cool in the baking tin for 5 minutes, then transfer to a cooling rack and allow to cool completely before decorating.
08 - In a bowl, beat the softened butter and cream cheese together until smooth using an electric mixer. Gradually add sifted powdered sugar while mixing on low speed. Blend in pineapple juice, vanilla extract, and yellow gel coloring if desired. Increase speed and whip until the frosting is light and fluffy.
09 - Once cupcakes are fully cooled, generously frost each using a piping bag or spatula. Garnish with dried pineapple flowers or maraschino cherries as desired.