Acorn flour.

Botanical name: 

Newsgroups: alt.folklore.herbs
Date: 03 Nov 1995 08:49:48 -0500
Subject: Re: Acorn flour?

Ripe acorns, (white oak is sweeter than black or red)
Remove the cups and shells
I prefer to boil them 2-3 hours, changing the water when it becomes brown, then roast 350 degrees for approx. 1 hour (taste test).
When they have cooled, grind in a food processor or as back in the old days chop, pound, and roll with a rolling pin. Grind as fine as you can.
One book suggests after the first grinding dry the flour in the oven again for ½ hour. I don't do this, but if the flour is still moist it would be a good idea. Also, you have the option of combining the acorn flour with other flours.