With a mixer, beat heavy whipping cream until thick. Fold a cup of it into a bowl with the sweetened condensed milk, add optional vanilla and mix until smooth.

Pour sweetened condensed milk/whipping cream mixture back into the bowl with the heavy whipping cream and fold together until smooth and creamy.

Next, pour half of the ice cream into a freezer safe container. Add half of the berry pie filling and use a spoon or a knife to swirl the mix-in together with the ice cream (optional).

Top with remaining ice cream, and then top that with the remaining berry pie filling.

Freeze for 5-6 hours or overnight. When it is time to serve, remove from freezer and let sit on the counter to soften for 5-10 minutes prior to serving.