Preheat oven to 325 degrees.

Crust

In a small bowl, mix together chocolate cookie crumbs and melted butter. Press into bottom of springform pan and set aside.

Filling

Place the cream cheese in the bowl of a stand mixer and beat on low speed until smooth and creamy. Add eggs one at a time, beating on low speed after each until just combined. Scrape down the sides of the bowl after each. Add sugar and beat on low speed until creamy, about 2 minutes. Add sour cream and Kerrygold Irish Cream Liqueur and beat on low speed until combined.

Pour filling into prepared springform pan. Fill a baking dish halfway with boiling water and place on lowest rack of oven. Place cheesecake on middle rack of oven and set timer for 55 minutes.

Turn oven off and leave cheesecake in oven for one hour. After one hour, remove cheesecake from oven and cool completely on a rack.

Wrap and chill for at least 4 hours.

Chocolate Sauce

Heat whipping cream on stove until hot, but not boiling. Add chocolate chips and stir until melted. Add Kerrygold Irish Cream and whisk until blended.