Preheat the oven to 375°F (190°C). Line a baking sheet with parchment paper.
Prepare the churro bites: Roll out puff pastry on the sheet. Brush with melted butter, sprinkle with cinnamon sugar, and cut into small squares.
Bake for 12–15 minutes or until golden and crisp. Let them cool completely.
Whip the cream to stiff peaks using a mixer.
In another bowl, mix sweetened condensed milk, vanilla extract, and cinnamon.
Fold the whipped cream into the condensed milk mixture until smooth.
Layer in a container: Add a layer of the ice cream base, a handful of churro bites, and repeat. Optionally swirl extra cinnamon sugar between layers.
Freeze for at least 6 hours, or overnight for best texture.
Serve and enjoy!