Prepare the Base Mixture:

In a medium mixing bowl, whisk together the sweetened condensed milk and malted milk powder until smooth and no lumps remain. Press any stubborn lumps against the side of the bowl with your whisk.

Add the vanilla extract and kosher salt to the mixture. Whisk until completely incorporated and set aside.

Whip the Heavy Cream:

Pour the chilled heavy cream into a large mixing bowl. Using an electric mixer on medium-high speed, whip the cream until stiff peaks form, about 4-5 minutes. The cream should hold its shape firmly when you lift the beaters.

Combine the Mixtures:

Add about one-third of the whipped cream to the condensed milk mixture. Gently fold together with a rubber spatula to lighten the base.

Add the remaining whipped cream and fold gently until no streaks remain, using a lifting and turning motion to maintain airiness. Avoid over-mixing to keep the texture light and creamy.

Freeze:

Transfer the mixture to a metal loaf pan or freezer-safe container. Smooth the top with a spatula.

Press plastic wrap directly onto the surface to prevent ice crystals, then cover the entire pan with aluminum foil.

Freeze for at least 8 hours or overnight until firm.

Serve:

Let the ice cream sit at room temperature for 5 minutes before scooping. Sprinkle with flaky finishing salt just before serving if desired.