In a small saucepan, combine 1/2 cup sugar, 5 tablespoons flour, a pinch of salt and a 1 tablespoon of matcha powder. Stir in milk, a little at a time, until smooth. Bring to a boil over medium heat, stirring constantly. Boil 60 seconds, then pour a small amount of hot liquid into the 2 egg yolks, and stir. Then return now heated egg yolks to saucepan and stir, over heat, until mixture starts to bubble again. Remove from heat, add vanilla. Cover and chill in refrigerator. Preheat oven to 450 degrees.
In a medium saucepan, combine shortening and green tea and bring to a boil. Sift together 1 cup flour and a pinch of salt and pour all at once into boiling mixture. Stir vigorously until mixture forms a ball. Remove from heat, and add eggs, one at a time, stirring vigorously after each addition. Drop by spoonfuls onto baking sheet, or pipe into desired shape.
Bake 10 minutes in the preheated oven, then reduce heat to 400 degrees and bake 25 minutes more, or until golden. Cool completely, split, fill with custard, and replace tops.