Add the rolled oats to a blender, food processor, or spice grinder and blend into a powder.Depending on the amount you're grinding, you may need to do it in batches (especially if using a spice grinder).When using a blender/food processor, stop the machine occasionally, give the jug a jiggle to get all the oats back to the bottom, and continue to blitz until you have a fine powder.
For very fine flour, then sieve the mixture and re-grind/blend the larger bits if necessary.
When ready, use immediately or transfer the flour into a large airtight glass jar.
How To Store
Homemade oat flour can be stored for several months (3-4) in a cool, dry location.The shelf life will also depend on how fresh the oats are in general and their BBE date, so note that before blending it into oat meal flour.
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Notes
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