Place chocolate chips and espresso powder in a microwave safe bowl. Set aside.
In a small saucepan over low heat, heat 1 cup of the heavy cream until scalding (not boiling!). Remove from heat and pour onto the chocolate chips.
Allow mixture to sit for 5 minutes, then stir with a whisk to combine. By this point, chocolate should be fully melted. If it’s not, place in the microwave for 15 seconds and stir. Spoon into a piping bag and place in the fridge until ready to layer.
In a standing mixer fitted with a whisk attachment, beat the remaining 2 cups of heavy cream until soft peaks form. Add the powdered sugar, vanilla extract and salt and beat well. Set aside.
Line the inside of a standard-sized loaf pan with plastic wrap on all sides. Working in layers and starting with the whipped cream mixture, spoon and spread the whipped cream, pipe and spread the ganache, and dunk Oreo cookies in coffee before layering on top of the fudge. It’s completely up to you how much you spoon on each layer– if you want more whipped cream, do it! More chocolate, do it!
Repeat layers until your loaf pan is full, finishing with a layer of whipped cream.
Cover with plastic wrap and place in the freezer to set for at least 3 hours.
When ready to serve, take the icebox cake out of the freezer. Beat the heavy cream with a whisk until medium-stiff peaks form. Add the powdered sugar and beat well. Last, fold in the Oreo cookie crumbs until evenly distributed.
Remove ice box cake from the loaf pan and place on a serving tray. “Frost” with the whipped cream, using a spoon to make big swirls. If desired, top with crumbled cookies. Use a hot, sharp knife to slice and serve! Enjoy.