Preheat your oven to 350 degrees.
Whisk together flour, salt, and baking powder in a mixing bowl.
In another mixing bowl, combine the butter and sugar.
Once the mixture is light and fluffy, add the eggs, one by one.
Mix until combined.
Add the Hennessy and milk to the mixture.
Mix the dry and wet ingredients, until combined.
Pour the batter into a cake pan.
Bake for 30-50 minutes.
Set it aside and let it cool.
For the frosting, beat the butter until smooth in another bowl.
Add the sugar slowly, mixing well.
Add the Hennessy and vanilla extract. Beat until smooth.
Frost the top of your cake and serve immediately.