Preheat oven to 350°F. Grease and flour a 9-inch round cake pan.
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
In a large bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs, one at a time, then add in the vanilla extract, coconut milk, lime juice, and lime zest. Beat until combined.
Gradually add the dry ingredients to the wet ingredients and mix until just combined. Gently fold in the shredded coconut.
Pour the batter into the prepared cake pan and bake for 30-35 minutes, or until a toothpick inserted in the center comes out clean. Allow the cake to cool in the pan for 10 minutes, then turn it out onto a wire rack to cool completely.
In a medium saucepan, whisk together the cornstarch and heavy cream until combined. Place the saucepan over medium heat and bring the mixture to a boil, whisking constantly. Reduce the heat to low and simmer for 2-3 minutes, or until thickened. Remove the pan from the heat and stir in the powdered sugar and lime juice. Set aside and allow to cool.
Once the cake is cooled, place it onto a serving plate and spread the frosting over the top. Sprinkle the remaining shredded coconut over the frosting and serve.
Interesting Facts
Coconut milk is made from the flesh of a mature coconut.
Lime juice is a great source of vitamin C.
Lime zest is the outermost layer of the lime peel and is rich in flavor.