Preheat oven to 350°F. Line cupcake pans with cupcake liners.
Whisk salt, baking powder, and flour in a medium sized bowl. Set aside.
Using a hand mixer, cream sugar into softened butter until fluffy, about 1-2 minutes. Beat in eggs, one at a time, then mix in vanilla extract.
Add dry ingredients alternately with the coconut milk, starting and ending with the flour, mixing gently between each addition. Mix until just combined. Be sure to scrape the sides of the bowl.
Stir in ½ cup shredded sweetened coconut.
Pour batter into prepared pans and bake approximately 12-18 minutes, or until a toothpick comes out clean. Cool completely before removing and frosting.
To make the frosting, beat butter in a large bowl with a hand mixer until smooth.
Slowly beat in powdered sugar until crumbly. Beat in salt and extracts. Add coconut milk, 1 tablespoon at a time, until you reach your desired consistency. Frost cupcakes as desired, sprinkle with additional shredded coconut.