Preheat the oven to 350 F/ 180 C/ gas mark 4. Lightly grease a 20 cm (8'') spring form pan and line the bottom with parchment paper. Lock the sides.
In a food processor pulse the desiccated coconut until it resembles fine breadcrumbs. Combine with the flour, baking powder, cocoa and salt. Stir thoroughly using a whisk.
Beat together the eggs, sugar, vegetable oil, coconut milk and vanilla extract until fluffy and pale (2-3 minutes). Gradually add half of the dry mixture and fold in the remaining mixture using a spatula just to combine. Do not overstir.
Scrape the batter into the pan and bake in the centre of the oven for 45-50 minutes or until a toothpick inserted in the middle comes out clean.
Remove from the oven and set aside to cool for 20 minutes, then run a spatula around the cake and carefully remove the ring. Cool completely before decorating.
In a microwave melt the chocolate pieces almost completely and stir in the coconut oil until smooth. Drizzle over the cake and decorate with lightly toasted coconut flakes.
Use either cocoa or cacao powder. I tend to use cacao as it's a little healthier.
I recommend pulsing the desiccated coconut until it resembles fine breadcrumbs before adding into the batter. This will improve the texture of the cake.
Do not overstir the batter. Stir just to combine.
Allow the cake to cool completely before decorating and cutting (it will cut better).