Preheat the oven to 160 C (325 F) and grease 2 10 inch cake pans.
In a large sized bowl, beat the sugar, butter, oil and the vanilla extract with an electric mixer until it is all blended. Add the egg yolks one at a time until it is well mixed together.
In a different bowl, mix the, baking soda, baking powder, flour and salt . Combine all ingredients. Then, add to the butter mix. Mix in the buttermilk until it is well mixed. Make sure to fold in the coconut.
Whip the egg whites in a clean bowl and cream of tartar on a high speed until it is in a stiff form. Mix in about a fourth of the egg whites with a whisk into the butter mix and then fold in the rest of the mixture
Pour the batter into the cake pans and bake until a toothpick has been inserted and has come out clean. Cook for about 25 minutes. Remove from the oven after 25 minutes and let it cool for about 10 minutes before removing the cake from the cake pans. Transfer the cake to a cooking rack and let it cool completely