I found a recipe on here: 

1 1/2c   Cake Flour

1/3c      Butter

1 1/4t    BP

1          Egg

3/4t      Salt

3/4t      V. Extr

3/4c      Sugar

2/3c      Milk

This is actually 1/2 the recipe, anyhow, it doesn't seem moist at all to me. How can moisten it? 

AUse a wash.

Add fat.  This cake is great!

try 

1 1/2 cups sifted cake flour

1/2 cup butter unsalted

1 1/2 tsp BP

1/4 tsp salt

1 cup sugar

2 eggs

1 tsp vanilla

1 cup plus 2 Tbsp full fat buttermilk