Preheat the oven to 175°C (350°F) and prepare a sheet cake pan with grease and parchment paper.
Mix flour, baking powder, and salt in a bowl.
Beat butter, sugar, eggs, and vanilla extract until light and creamy.
Add coconut milk and dry ingredients gradually, mixing until a smooth batter forms.
Fold in shredded coconut and pour the batter into the prepared sheet pan.
Bake for 30–35 minutes until golden and a toothpick inserted comes out clean.
Cool completely, spread with coconut frosting, and garnish with shredded coconut before serving.