Black Glutinous Rice Cookies

These cookies are modification from my recent cheese cookies i only substitute half of sago flour with black glutinous rice flour, which also very hard to find in Taiwan. So, i attempted to make my own flour, since the rice easily available. Using vitamix high performance blender, it took less than 10 minutes to mill the rice into flour.
I was thinking about milling my own sago flour, but where can i get the sago palm..??? hahaa... kidding.