In a large mixing bowl, mix butter and sugar until smooth. Add eggs and oil. Mix until smooth.
Add vanilla extract, Irish cream, milk, and water, mix until blended.
Add dry ingredients, mix until smooth.
In two 8 inch cake pans lined with parchment paper at the bottom, pour cake batter evenly.
Bake at 300 F for 30-40 minutes until insert in the centre of the cake comes out clean. One cake might take slightly shorter or longer than the other.
Cool completely for 2-3 hours before icing.