Preheat oven to 350 degrees and prepare a loaf pan with non-stick cooking spray.
In a large mixing bowl, cream the butter and sugar together.
Add the egg into the mixture and mix until combined.
Then, add the milk, vanilla, and whiskey.
In a medium bowl, combine the flour, cocoa powder, baking soda, baking powder, and pinch of salt.
Add cocoa mixture to wet ingredients and mix until combined. If batter is too thick, add a little milk at a time. Then, fold in the chocolate chips.
Pour the batter into the prepared loaf pan and bake for an hour, or until a toothpick comes out clean from the center of the loaf.
Allow the loaf to cool completely. Then, spread a layer of chocolate frosting on top.
If desired, add green sprinkles on top.
Cut into slices and serve.