Combine the heavy whipping cream with 2 cups of the cereal. Cover and refrigerate for at least 2 hours or overnight.
Strain the cream and discard the soaked cereal. Measure 2 cups of the infused cream into a large mixing bowl. If needed, add more heavy whipping cream to make 2 cups.
Add the vanilla extract. Beat with a stand mixer or hand mixer until soft peaks form.
In a separate bowl, stir together the sweetened condensed milk, cinnamon, and sugar.
Gently fold the sweetened condensed milk mixture into the whipped cream until combined.
Fold in the remaining 1 cup of cereal.
Spread the mixture into a loaf pan. Cover and freeze for at least 4 hours, or until firm.
Serve and enjoy.
Notes
I place my mixing bowl and beaters in the freezer for 10-15 minutes before whipping the cream to help whip it quicker.