Add the condensed milk, whipping cream, and vanilla extract to a mixing bowl. Keep whisking over slow speed until combined. Increase the speed until the mixture becomes fluffy and light.
Smash your biscuits or cookies into tiny bits with a mortar and pestle. Alternatively, put your cookies in a ziplock bag, place them on top of a flat surface, and use the baking roller to smash them into crumbs.
Add the crumbs to the ice cream mixture.
Slowly pour the espresso into the mixture and start folding everything until combined.
Transfer the mixture to an air-tight container. Pop it in the freezer and let it chill for at least five hours before serving.
