1/3cupIrish whiskeyJameson is my favorite, although 2 Gingers—what you see in the photos—is also good, and a bit less expensive; if you like, you swap and whiskey, bourbon, or even rum you prefer. To make the cake non-alcoholic, use brewed, cooled coffee
Place a rack in the center of your oven and preheat the oven to 375 degrees F. Grease an 9-inch round cake pan, line the bottom with a circle of parchment paper, then grease again. Set aside.
In a large heatproof mixing bowl set over a pan of simmering water (or in a microwave-safe bowl in 15-second bursts), melt together the chocolate and butter. When the chocolate is almost completely melted, remove it from the heat and stir until completely melted and smooth.
With a mixer on medium-low, slowly add the sugar and salt and mix until smooth. Mix in each egg, one at a time, combining fully between each addition and stopping to scrape down the sides of the bowl as needed.
Sift the cocoa powder into the bowl, then add the vanilla extract and whiskey. Mix on low until well combined. The batter will be thick, smooth, and glossy.
Transfer the batter into the prepared pan, smooth the top, and bake for 18-22 minutes, until a toothpick inserted into the center comes out mostly clean with just a few crumbs clinging to it. (Do not overbake or the cake will be dry!)
Allow the cake to cool in the pan for 5 minutes, run a butter knife around the edge, then gently invert the cake onto a serving plate.
While the cake cools, prepare the chocolate ganache. In a small saucepan or a microwave-safe bowl, melt together the chocolate and butter until just a few pieces of chocolate and butter remain. Remove from the heat, then continue stirring until the two are completely melted and smooth. Stir in the whiskey and salt, then spread over the cooled cake.
To make the sprinkle shamrock: While the ganache is still wet, lightly place the shamrock cut out on the cake's surface in the center. With a toothpick or the point of a sharp knife, lightly trace around the shape so that you leave a faint outline in the glaze. Carefully lift off the paper. Fill in with colored sprinkles.
For clean slicing, refrigerate the cake for a few hours. For immediate (messy) slicing, dive in right away.
INGREDIENTNOTE: Because this cake has so few ingredients, the quality of chocolate that you choose is ultra important. Be sure to pick a good brand.