Pre-heat oven to 330 degrees Fahrenheit. Cream the butter, salt and sugar in a bowl until light in color.
Add the eggs one at a time, make sure to scrape the sides and bottom of the bowl in every addition. Add in the vanilla extract.
Combine the all-purpose flour, cake flour and baking powder.
Combine the milk and dissolved coffee.
Add half of the dry ingredients to the egg mixture, beating just until incorporated followed by the wet ingredients and the rest of the dry ingredients again. Mix just until incorporated.
Divide into three 5 inches round pan and bake for 30 minutes.