Irish Mocha Brownie Shooters

Brownies: Prepare brownies according to package instructions, substituting strong coffee or espresso for water. Bake in mini muffin tins (coated with nonstick spray) for about 12 minutes or until still very soft, but done in the middle. (Do not overbake, or you'll get really crunchy little brownies.)
Icing: While brownies are cooling, place butter in a large bowl. Using either a hand mixer or stand mixer, whip butter at increasing speed until it is light and fluffy. Add sugar, one cup at a time, mixing on low speed. Once icing starts to thicken, start adding Bailey's a little at a time and blend until smooth. You may have to alternate between sugar and Bailey's until you get a good texture. If it forms nice peaks and holds its shape, it's perfect. Once brownies are cool, split each carefully and fill with icing. Place tops back on and give each another swirl of icing.
Ganache: Put chocolate in a small heatproof bowl. Heat heavy cream in a small pan over low/med heat until it simmers. Remove from heat and pour over chocolate; stirring constantly until melted and smooth. Add whiskey to taste; stir. Allow ganache to cool until it reaches a glaze-like consistency. Drizzle over cupcakes using a spoon or piping bag. (Makes 24 mini brownies.)