If you’ve never tasted acorns, do yourself a favor and cook some up, then share your creation with a friend. It’s time acorn eating became common again.
There are myriad ways to process acorns and leach out the tannins before eating. Here are the basics for the cold-leaching method that preserves the starch and gives the flour a more gluten-like quality excellent for thickening sauces and baked goods. If you’d prefer the “semi-homemade” approach, look for acorn flour at your nearest Asian market.
Basics: Understanding the nuances of this process are a life’s work. Please consult Samuel Thayer’s Nature’s Garden or Beverly R. Ortiz’s book (as told by Julia F. Parker) It Will Live Forever: Traditional Yosemite Indian Acorn Preparation, two excellent resources, for more details.
- Collect acorns. Pick up acorns off the ground, choosing those with no caps and no weevil holes.
- Immediately lay the acorns out in a single layer in stacked cardboard boxes or on screens, and let them dry out gently. Once dry, they will keep for years.
- Crack them at your leisure (see Resources for techniques) and then pry the nutmeats from their shells.
- Winnow the papery sheaths from the meats on a windy day; partial removal is OK. Soak the nutmeats in water overnight, or until softened, in the fridge.
- Blend them into fine- to medium-grain flour with a food processor. Put the wet, ground flour into a large container.
- Top off the flour with cold water and cover. Leave this in the fridge, decanting the water and replacing it every day for up to several weeks, until the flour tastes palatable.
- It should be earthy and bland, with only a slight astringency in the background, no more. Your flour is ready to use. Store it in reasonably sized portions in the freezer. I recommend storing the bulk of your acorns dried in the shell and making flour in batches, as needed.