Preheat oven to 180 and line and grease 2 round cake tins

For the cake- In one bowl sift the flour, baking powder and baking soda

In another bowl combine the sour cream and milk and set both bowls aside

In a separate bowl beat the sugar and butter until light and fluffy

Add the egg whites and the vanilla to the butter mixture and combine

Add half of the flour mixture to that and combine, then Add the sour cream and milk mixture until combined. Then add the remaining flour mixture and mix

Pour evenly between the two tins and bake for around 25-30 minutes

For the vanilla cream- beat the butter until smooth then add the rest of the ingredients and mix until creamy and smooth

Once the cake is cooked and cooled sandwich it with the cream and cover the cake fully if desired