In a medium saucepan, heat the Heavy Cream and Whole Milk over medium heat until it begins to steam and small bubbles form around the edge — do not boil.
While the dairy warms, whisk the Egg Yolks with the Granulated Sugar in a bowl until the mixture lightens in color and thickens slightly.
Slowly temper the egg mixture by whisking in a ladleful of the hot cream-milk, then gradually add another 1–2 ladles until the yolks are warmed through and smooth.
Pour the tempered yolk mixture back into the saucepan and cook gently over low heat, stirring constantly, until the custard thickens enough to coat the back of a spoon (about 170–175°F or when it leaves a clear line when you run your finger across the spoon).
Remove the pan from heat and strain the custard through a fine-mesh sieve into a clean bowl to remove any cooked bits; stir in a pinch of Fine Salt to enhance the flavors.
In a small bowl, whisk the Matcha Powder with a little Hot Water to form a smooth, lump-free paste, then whisk this matcha slurry thoroughly into the warm custard until evenly blended and vibrantly green.
Cool the mixture quickly by placing the bowl in an ice bath, stirring occasionally, then cover and chill in the refrigerator for at least 4 hours or preferably overnight to develop flavor.
Once fully chilled, churn the custard in an ice cream maker according to the manufacturer’s instructions until it reaches a soft-serve consistency, then transfer to a lidded container and freeze for at least 2–4 hours to firm up.
When ready to serve, let the ice cream sit at room temperature for 5 minutes to soften slightly for easier scooping; garnish with a light dusting of additional matcha if desired.
