You can substitute the oil with melted margarine or butter, have done it both ways and both turned out great. Sometimes some oils are dense/heavy or have a weird oily smell, I find butter/margarine a safer option for most recipes. :)
1 cup castor sugar
1 tsp. vanilla essence
½ cup cocoa powder ½ cup oil or melted butter/margarine
1 ½ cup flour
2 tsp. baking powder
Ingredients for filling
2 egg white
1 cup desiccated coconut
½ cup icing sugar
Beat eggs n sugar till creamy. Add vanilla essence n oil n beat for 1 min. In a separate bowl sieve flour, baking powder n cocoa powder. Fold dry ingredients in egg mixture.
For filling: Beat egg whites till stiff peaks form, add in icing sugar n beat for another 2 mins add coconut and fold.
To assemble: Grease baking pan pour half of cake mixture in the pan and level it pour filling n level. Pour the remaining cake mixture and level. Bake in a preheated oven at 180 C for 30 mins or till done remove from oven let it cool completely in the tin before turning it out.