Line 18 muffin cups with liners and preheat the oven to 350 degrees.
Whisk together flour, baking powder, and salt and set aside.
Use an electric mixer to beat butter, sugar, vanilla extract, and mint extract until creamy.
Beat in eggs one at a time.
Combine milk and bourbon in a large liquid measuring cup.Add flour mixture to butter mixture in 3 additions, alternating with milk mixture in 2 additions.
Fill each muffin cup 3/4 of the way full.Bake for 22 to 25 minutes or until a toothpick inserted in the middle comes out clean.
To make frosting, beat butter, vanilla extract, mint extract, and bourbon until creamy.
Beat in the powdered sugar, heavy cream, and green food coloring.
Fill piping bag with frosting and pipe it on the cupcakes.
Notes
You can use salted butter and use a pinch less salt.