Preheat the oven to 350℉ (180℃). Grease your cake pans, line the bottoms with parchment paper, and dust the sides with flour for easy removal later.

Cream the butter and sugar in a mixer until light and fluffy, about 2-3 minutes.

Add one third of the beaten eggs and mix at medium speed until well combined.

Combine one third of the sifted flour into the mixture, mixing gently. Repeat this process until all eggs and flour are fully integrated.

Mix on low speed and add the remaining flour and Irish whiskey, blending until just combined.

Divide the batter evenly between the prepared cake tins, smoothing the tops. Bake for about 35 minutes or until a toothpick comes out clean.

Cool the cakes in the tins for 15 minutes. Carefully remove them to a wire rack to cool completely.

Prepare the whiskey buttercream by mixing all buttercream ingredients until smooth and fluffy.

Level the tops of both cake layers to ensure they stack evenly.

Assemble the cake by placing one layer on a serving plate, spreading a generous amount of whiskey buttercream over it, and topping it with the second layer.

Make the whiskey glaze by heating all ingredients except whiskey in a pot over medium heat until boiling, then simmer for 2-3 minutes.

Remove from heat, let it cool slightly, and stir in the whiskey.

Pour the glaze over the cake, allowing it to drip down the sides.

Decorate as desired and serve.