You’ll want three different size star-shape cookie cutters to make this tree.
Sift the flour, matcha, and baking powder together in a bowl.
Place the butter in a bowl and, using an electric mixer, mix it until it is smooth. Add the sugar in parts (one-third to one-half at a time) until it is fully mixed into the butter and the entire mixture is white and smooth.
Beat the egg and vanilla extract into the butter little by little. Once they are both incorporated, fold the flour mixture into it in parts (one-third to one-half at a time). When fully mixed in, wrap the dough in plastic wrap and place in the refrigerator to chill for 30 minutes.
Preheat the oven to 360 degrees F.
Lightly flour a working surface and roll out the dough until it is about 1/10-inch thick. Using small, medium, and large star-shaped cookie cutters, cut stars out of the dough. Place the cut out dough on a cookie sheet and bake for about 10 minutes. Allow to cool.
In a separate bowl, mix the powdered sugar and egg whites for the icing.
Stack the small cookies on the medium cookies on the larger cookies, using the icing as a glue to hold them together.
Accent with any decorations you like.