Chill a stand mixing bowl in the fridge for 20 minutes.
In a medium bowl, combine together the condensed milk and vanilla extract.
Pour the cold heavy whipping cream into a bowl of a stand mixer fitted with the whisk attachment. Sift in the matcha powder. Start whipping on slow speed and gradually increase the speed until soft peaks.
Continue to whisk until almost stiff peaks.
Remove about ⅓rd of the whipped cream and add it to the condensed milk. Use a spatula to fold in the whipped cream to lighten up the mixture.
Add the lightened condensed milk back into the remaining of whipped cream and use a whisk to fold the mixture together until homogeneous.
Transfer the mixture into clean pint-sized jars. Gently tap to release any bubbles.
Place into the freezer for at least 2 hours for soft-serve consistency, and 6 hours for hard ice cream.