In the bowl of a stand mixer fitted with the whisk attachment, whip the heavy whipping cream and the sugar on HIGH speed for about 5-7 minutes or until stiff peaks form. While the mixture whips, in a medium bowl, combine the sweetened condensed milk and creamy peanut butter until blended.

Fold the peanut butter milk mixture into the whipped cream until just combined. Pour half of the mixture into a freezer-safe container with a lid. Sprinkle liberally with half of the peanut butter cups and drizzle with half of the hot fudge sauce. Repeat layers, pop on the lid (or cover with plastic wrap), and freeze for at least 8 hours, preferably overnight.