Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 10 inch Bundt pan.
In a large bowl, stir together cake mix and pudding mix. Make a well in the center and pour in oil, sour cream and eggs. Beat on low speed until blended. Scrape bowl, and beat 4 minutes on medium speed. Stir in the coffee liqueur and chocolate chips.
Pour batter into prepared pan.
Bake in the preheated oven for 45 minutes, or until a toothpick inserted into the center of the cake comes out clean. Allow to cool.
Spread with Chocolate Glaze.
For Chocolate Glaze: In a saucepan, melt together the butter and chocolate chips, stirring frequently. Cool slightly, then quickly spoon over cake.
