Preheat the oven to 350F. Line a sheet pan with parchment paper.
Whisk the confectioner’s sugar and green tea together in a bowl.
Add the butter and green tea/sugar mixture to the bowl of a stand mixer fitted with the paddle attachment. Mix until smooth and light in color.
Add the flour and mix until well combined.
Add the egg yolks and mix just until the eggs are fully incorporated and a mass forms.
Form the dough into a disk and chill in the refrigerator until firm (about 30 minutes).
Roll the dough out to ½” thickness.
Cut the dough with a leaf cookie cutter. (I don't have that cutter so I picked my pear shape :p)
Place the sugar-coated cookie on a parchment lined pan. Bake at 350F for 12-15 minutes, or until slightly golden around the edges.