Preheat oven for 180.c
Sieve all purpose flour and baking powder.
Grate the orange zest.
Take a bowl add egg,sugar powder,milk,butter,vanilla essence,orange zest and orange juice and mix well.
Mix until light and fluffy.
Add the dry ingredients into wet ingredients and mix well.
Pour the mixture into the cake tin and bake for about twenty mins
Insert the toothpick and check the cake.