Preheat oven to 400 degrees.
Mix together flour, sugar, salt, and baking soda.
In a saucepan, bring butter, cocoa, and water to a boil.
Pour over dry ingredients and mix well.
Add Baileys and eggs. Stir until completely mixed.
Pour mixture into greased and floured rimmed baking pan (11x17 inches).
Bake at 400 degrees for 20 minutes.
Start preparing icing 5 minutes before cake is done.
For icing:
Melt butter, cocoa powder, and Baileys in a medium saucepan over medium-high heat. Bring the mixture to a boil, stirring.
Remove from heat and stir in 2 cups powdered sugar.
Spread over hot cake.
Cool, cut, and enjoy!