Preheat oven at 350F. Grease a tart pan with a removable bottom.
Make the crust by mixing all the crust ingredients in a food processor, until the mixture resembles coarse meal. Press the mixture onto the bottom of the prepared pan. Bake crust for 15 to 18 minutes. Set aside to cool completely.
To prepare the ice cream, combine milk, heavy cream and 1/4 cup sugar, salt and 2 tablespoons matcha powder in a medium saucepan. Bring mixture to simmer, until sugar is dissolved. Remove from heat and set aside.
Whisk egg yolks and remaining sugar in a medium bowl until pale, about 2 minutes. Gradually whisk in half of the warm cream mixture, mix until blended. Stir yolk mixture into the remaining cream mixture. Cook over medium heat, stirring constantly, until thick enough to coat a wooden spoon, about 2 to 3 minutes.
Strain custard into another medium bowl, let cool over a bowl of ice water, or chill in the refrigerator, stirring occasionally, until it becomes cool.
Process custard in an ice cream maker according to manufacturer’s instructions. Few minutes before it’s done processing, add red bean paste while the machine is running.
Transfer ice cream on top of the tart crust. Keep the remaining ice cream in an airtight container, cover and freeze until firm, at least 4 hours.
Before serving, sprinkle matcha powder on top of the tart.