Preheat oven to 350 ℉ and place a rack in the lowest third of the oven. Spray a tube cake pan with cooking spray. Sprinkle cocoa powder in the pan and rotate the pan while tapping the sides to coat the pan with the cocoa. Place the tube pan on a baking sheet and set aside.
Place the sour cream, eggs, water, pudding mix, oil, and espresso powder (if using) in a large bowl. Use a hand mixer on low speed to combine thoroughly, about 45 seconds. Add the cake mix to the mixture and mix on medium-low speed until light and fluffy, about 2 minutes, scraping down the sides of bowl as needed.
Use a rubber spatula to fold the chocolate chips into the cake batter. Evenly spread the batter into the prepared tube pan. Place the baking sheet in the oven with the cake pan on top and bake for 35-45 minutes until a wooden pick inserted into the center of the cake comes out clean. Transfer to a wire rack and cool for 10 minutes.
Remove the cake from the bottom outer pan of the tube pan. Cool completely on a wire rack before removing the tube center and transferring to a serving plate.
Microwave the hot fudge and salted caramel jars (with the lids removed!) in 30-second increments until they are pourable.
Use a spoon to spread ½ cup of the hot fudge topping on top of the cooled cake. Drizzle the caramel on top of the fudge in a quick back-and-forth motion. Serve the cake immediately or store in the fridge for up to 5 days. The cake tastes wonderful warmed, at room temperature, or chilled! A scoop of ice cream on top is HIGHLY recommended!