In a medium bowl, whisk together the sifted matcha powder and the sweetened condensed milk until the matcha is completely smooth and there are no lumps remaining. Whisk in the vanilla extract and the pinch of salt.

In a separate large bowl, use an electric mixer (handheld or stand mixer with whisk attachment) to whip the cold heavy whipping cream until stiff peaks form. This usually takes 3 to 5 minutes.

Gently fold about one-third of the whipped cream into the matcha/condensed milk mixture using a rubber spatula. This lightens the base mixture.

Pour the lightened matcha mixture back into the remaining whipped cream and gently fold until just combined. Do not overmix; stop once no white streaks remain to maintain the airy texture.

Transfer the mixture to a freezer-safe container, such as a loaf pan or an airtight container. Cover the surface directly with plastic wrap to prevent ice crystals from forming.

Freeze for a minimum of 6 hours, or preferably overnight, until firm. Allow to sit on the counter for 5-10 minutes before scooping and serving.