Coastal Indians(Washington and maybe Oregon) used to put acorns into a small pit and pi** on them until they acquired a nice salty taste and then suck on them. Makes the old mouth water doesn't it?
My tribe shelled them and put them in a creak bed and let the water run over them for a long time then they would dry them in the sun, pound them with a pestle until made into a flour. Then make a bowl shape in clean sand on the river bank and put the flour in there and pour fresh water over and over it ( it’s called leaching it) Then they would make bread but mainly make a soup or much out of it.They cooked the mush in baskets made just for that by putting hot rocks into the mush and keeping the rock moving to heat it but not burn the basket. To eat them raw right out of the shell will make you sick, that is, if you can keep them in your mouth long enough to swallow, as they are pure bitterness.
I just remembered that there is a book at Amazon called “It will live forever”, by Julia Parker, an Indian lady from the Yosemite area. The whole book is on how the Indians prepared and cooked acorns. I’ve always wanted to try it but I live on Maui and we only have coconuts. They are good and you don’t have to cook them. LOL