Line the inside of your springform pan with an acetate sheet. Since the brownie layer is baked into the bottom at this point, feel free to nestle the acetate in between the brownie and the pan.
With the brownie completely cool, spread the coffee ice cream with an offset spatula on top. Make sure to get this layer as smooth as possible
Next, add the crumbs. I use about 3/4 of the crumbs here, save the rest for the topping (or a snack)
Then spread the vanilla ice cream on top, just as you did with the coffee ice cream
Place half assembled cake in the freezer for about 40 minutes so these layers can solidify, the vanilla layer must be solid and the fudge needs to be pliable yet cool when it hits the ice cream so it does not melt in the next step
Remove cake from freezer and top with espresso fudge. Spread evenly using an offset spatula. Optional: top with the remaining crumbs
Return cake to freezer for at least 4 hours, until it is fully set.
Remove from freezer, remove the ring around the springform and the acetate and enjoy!