That’s rice flour, my friend.  Ground in my very own kitchen!  My MIL got me this cool hand crank grinder for Christmas.  I wouldn’t recommend handcranking enough for a fat loaf of bread, but for a few cups here and there, it’s perfect.

I just clamp it to my kitchen table and turn the kids loose on it.

I have it as fine as it will go and the result is something akin to cornmeal.  Not as fine as all purpose flour, but plenty fine for cream of rice and pancakes!