For The Cake

1. Preheat your oven to 325°F. Liberally butter and then flour a 12-cup Bundt pan. Alternatively, you could use a good non-stick spray. 
2. Pour the chocolate chips into a medium microwave-safe bowl. Microwave on high for 15 seconds at a time, stirring after each time, until the chocolate is melted (or, melt on the stovetop per package directions). Allow it to cool a bit, so it won’t curdle the eggs when you add it to the cake batter later. 
3. In the bowl of your stand mixer fitted with the whisk attachment, beat the butter for 2 minutes on high speed until light and fluffy. Slowly pour in the granulated sugar. Cream the butter and sugar together until pale and fluffy; about 5 minutes. Add the eggs, 1 at a time, mixing well after each addition and scraping down the sides and bottom of the bowl as needed (rubber spatula!).
4. Reduce your mixer speed to low, and gradually add the flour in 2 batches, mixing just until combined. Add the cocoa powder, baking powder, and salt. Lastly, add the melted chocolate, the buttermilk, Irish cream, and the vanilla. Scrape down the bowl and mix the batter until just combined. 

For the Filling

Put the room temp cream cheese and sugar in the bowl of a stand mixer fitted with the whisk attachment and whip on high speed until the mixture is completely smooth and lump free. Add the egg, Irish Cream, and flour. Mix until totally smooth. Set aside for now.

To Assemble Your Cake

1. Pour half of the batter into the prepared Bundt pan. Going around the center of the pan, create a well of sorts. Pour the cream cheese filling into the well, ensuring the mixture doesn’t touch the sides of the pan. 
2. Pour the rest of the batter on top of the filling and spread it around gently to cover. Bake for 75 to 80 minutes, or until a cake tester/knife comes out clean. Let the cake cool in the pan on a wire rack for 15 minutes, then transfer to a plate, platter or cake stand. Let cool to room temperature. TIP: cover the cake with foil or plastic wrap so it does not dry out. Drizzle all over with the Irish cream glaze (see below). 

For the Glaze:

In a medium bowl, combine the confectioner’s sugar with the Irish cream and milk. Whisk until smooth and easily drizzled.