Preheat the oven to 350°. Line 12 muffin cups with FUN paper or foil liners.
Whisk together the cake flour, baking powder, baking soda, and salt.
Add in the eggs, sugar, oil, coconut and vanilla extracts and beat for 1 minute until combined.
Add half the flour mixture; beat on low speed. Combine coconut milk and vinegar. Add to batter; beat just until combined. Beat in the remaining flour mixture, then the remaining coconut milk mixture just until smooth.
Fill paper cups two-thirds full. Bake for 15-18 minutes or until cupcakes are golden brown and spring back lightly when touched. Cool on a wire rack.
For frosting, cream butter until light and fluffy. Beat in confectioners’ sugar, and then add the finely chopped pineapple and pineapple juice after beating in 2 cups of sugar. Add additional confectioners' sugar and pineapple juice to reach desired consistency.
Spoon frosting onto cupcakes. Top with toasted coconut and chopped macadamia nuts.
Do not substitute all-purpose flour. Cake flour is so magical in a white cupcake!
For topping, toast 1/2 cup sweetened flaked coconut by heating over medium-high heat in a small skillet for 3-4 minutes. Watch it very carefully, as it will start to toast quickly once it gets going. Or, toast in the microwave in a paper towel for 3-4 minutes, turning, until slightly brown.