Preheat the oven to 325°F and generously grease a 10” bundt pan with melted shortening.
Stir together the cake mix, pudding mix, eggs, water, oil, and rum until combined.
Pour batter into the prepared pan and bake for 1 hour.
Cool 10 minutes in the pan, then invert onto a serving plate.
Once cooled, glaze the cake.