Preheat the oven to 350°F and prepare two 8-inch cake pans.

In a medium bowl, mix together the gluten-free flour, corn starch, baking soda, baking powder, and salt.

In a separate bowl, mix together the granulated sugar, melted vegan butter, plain apple sauce, and vanilla extract until well combined.

Add the dry ingredients to the wet ingredients and mix until just combined.

Stir in the coconut milk and shredded coconut until the batter is well mixed.

Pour the batter evenly into the prepared cake pans and bake for 30 minutes.

Once done, remove the cakes from the oven and let them cool in the pans for 10 minutes before removing them from the pans and letting them cool completely on a wire rack.

In a large bowl, cream the softened vegan butter until it's light and fluffy.

Gradually add the powdered sugar, mixing well after each addition, until the frosting is smooth and creamy.

Add the coconut milk and vanilla extract to the frosting and mix until well combined.

Continue mixing the frosting until it's light and fluffy, about 2-3 minutes.

Once the cake layers are cooled, assemble the cake by spreading a layer of creamy coconut frosting between each layer of cake.

Use the remaining frosting to frost the sides and top of the cake, making sure to cover the cake evenly.

Once the cakes are cooled, assemble the cake by layering the cakes with the vegan coconut buttercream frosting. Once frosted, press the shredded coconut onto the frosted cake.