Pre-heat the oven to180°C/350°F/Gas Mark 4.
Line a 25cm square baking tin and a baking tray with parchment paper.
Place 100g of the desiccated coconut on the baking tray and bake for about 5 minutes until starting to brown. Remove from the oven and set to one side.
Place the Unsalted Whirl Butter Alternative, flour, sugar, baking powder, eggs, coconut milk and vanilla essence in a large bowl and mix with an electric mixer until light and fluffy.
Stir in the remaining 80g of desiccated coconut and turn out into the prepared baking tin.
Bake for 20-25 minutes until the cake has risen and is golden brown. Insert a skewer to check the middle is cooked it should come out without clean.
Remove the cake from the oven allow to cool for 5 minutes in the tin before turning out onto a cooling rack.
When the cake has cooled spread the jam on top and finish with a scattering of the toasted desiccated coconut.
Cut into squares and serve with some warm custard.