In a small bowl, sift the matcha powder to remove any clumps. Add hot water and whisk vigorously until smooth and frothy. Pour into a cup.
In a small saucepan, warm the milk over medium-low heat, stirring occasionally, until hot but not boiling.
Remove the saucepan from heat and add the chopped white chocolate.
Whisk continuously until the chocolate melts completely and the mixture is smooth and creamy. If you have a frother, froth white chocolate milk till desired creamy texture.
Pour the milk into the cup with the matcha mixture. Top with whipped cream or marshmallows, and dust with matcha for an elegant finish.
