Sometimes, Pastry Flour is hard to find. Pastry Flour can be All purpose flour. It will have a bit tougher in texture but no problem. Matcha powder should be not sweeten. Over mixing will result in making the scone cakey. In order to have the signature flakiness, unsalted better, heavy cream and egg yolk should be chilled until ready to use. Matcha is one of the most sensitive ingredients I have ever baked. Matcha should be kept air tight containers and cool temperature. Matcha can oxidized and change in flavor. Rather keeping finished product, keep the dough in the refrigerator upto 3days. Bake when you are ready to eat!