Acorns didn't make it into my foraging challenge last year, but they were something I'd been meaning to try. The trouble is, they have so much tannin in them that they're inedible raw. A typical guide to eating acorns calls for lots of soaking and drying to remove the tannins, and then further drying and grinding to make acorn flour, so I never got round to it.
Then this spring, while digging over the garden, I kept coming across sprouted acorns. I discarded a lot of these before I started to wonder whether sprouting might improve the flavour. I know that many seeds turn their starch into sugar when they sprout. I cautiously nibbled one and sure enough, it was sweet. Furthermore, the winter weather had done the job of all that soaking, and leached out most of the bitter tannins.
After that, I started looking out for sprouted acorns and collected them. Some had sprouted quite a lot.
I left them sitting on my kitchen counter for quite a while, so some of them dried out a fair bit, and those were pretty tough. I decided to boil them to soften the hard ones, and judging by the colour of the water I discarded, that removed some more of the tannins. I sliced them into a couscous salad, and they were really nice. Still a little on the chewy side, but that's no bad thing. I think those squirrels are onto something when they bury nuts - it's not just storage; it improves the flavour too.