Preheat the oven to 350° F and line a regular-sized muffin tin with cupcake papers.
In a small bowl, sift together the flour, baking powder, and salt. Set aside.
1-3/4 cups all-purpose flour, 2 tsps. baking powder, 1/2 tsp. table salt
In a pourable measuring cup, combine the egg whites, coconut milk, coconut rum, and coconut extract.
3 egg whites (from 3 large eggs), 1/2 cup full-fat unsweetened coconut milk, 1/4 cup coconut rum, 2 tsps. coconut extract
In a stand mixer, cream together the sugar and butter until light and airy, about 4 minutes on medium speed. Gradually add the dry and wet ingredients alternately, starting and ending with the dry ingredients, in three additions. Mix in the shredded coconut until fully combined, being careful not to over-mix the batter.
3/4 cup granulated sugar, 1/2 cup unsalted butter, 1 cup sweetened, shredded coconut
Fill each prepared muffin cup about ⅔ full with batter. Bake for 20–25 minutes, or until a toothpick inserted in the center comes out clean. Let the cupcakes cool in the pan for about 5 minutes before removing and cooling completely on a wire rack.
To make the frosting, beat the cream cheese and butter with a mixer until smooth, about 4 minutes. Add the coconut extract and powdered sugar, and beat until well combined. Spread the frosting on each cooled cupcake and top with shredded coconut.
8 oz. full-fat cream cheese, 1/2 cup unsalted butter, 1 tsp. coconut extract, 2 cups confectioners' sugar