Instructions

  1. Preheat oven to 350 degrees F.
  2. Line 18 muffin cups with liners.
  3. In bowl, mix cocoa and hot water until dissolved; reserve.
  4. Melt 6 T butter; reserve.
  5. In bowl, mix flour with next five ingredients.
  6. Whisk in buttermilk, eggs, melted butter and cocoa mixture.
  7. Stir in chips.
  8. Divide among liners.
  9. Bake 18-22 minutes or until toothpick inserted comes out clean.
  10. Cool 10 minutes.
  11. Transfer from pan to racks; cool.
  12. On medium-high speed, beat remaining butter until fluffy.
  13. Gradually beat in confectioners' sugar until blended.
  14. Add liqueur; beat until light and fluffy, 2 minutes.
  15. Beat in 1/8 t food coloring until blended.
  16. If desired, fit large star tip into pastry bag.
  17. Using paintbrush starting at tip of bag, paint 2-3 lines of food coloring along inside, ending 1 inch from edge.
  18. Place bag in glass; fill with frosting.
  19. Pipe, or with spoon, spread frosting over cupcakes.
  20. If desired, decorate with shamrocks.