Heat oven to 350°F.
Line cupcake pan with paper liners for 18 cupcakes
Beat butter, sugar, eggs and vanilla in large bowl until fluffy.
In separate bowl combine flour, cocoa, baking powder, baking soda and salt.
Add alternating flour mix and buttermilk to mixture, beating just until smooth.
Pour batter into prepared cupcake pan.
Bake 20 to 30 minutes or until wooden pick inserted in center comes out clean.
Cool completely before frosting.
Baileys Irish Cream Frosting
Beat butter and icing sugar together until fluffy.
Add 7 tablespoons of Baileys Irish Cream, beat until well combined.
If necessary add more Irish Cream until spreadable consistency.
White Chocolate Shamrocks
Melt 1 cup white chocolate in double boiler or microwave (50% power). Spread evenly onto parchment paper.
Before chocolate cools, dip tip of toothpick into green food colouring gel. Then using tip of toothpick make swirls into the chocolate.
Let cool, then cut out with Shamrock shaped cookie cutter.
You may have to cool in refrigerator for short time to harden enough to cut shapes.