Making oat flour at home is super easy and MUCH cheaper than buying a package of it at the store. If you have a good strong blender (like a Vitamix, Blendtec, or even a Ninja), you will be able to make your own oat flour.
Remember that when you ground down the oats, the volume you have left will be less. So, make sure you blend enough if you have a certain amount you need for a recipe. I add about 1/4 cup more oats for each cup of oat flour I need.
Simple place any kind of oats–old-fashioned or steel-cut— into your blender. Cover the blender with the top–securely! Turn your blender to the highest speed (slowly). Use the tamper if you have one to move the flour around as it is blending, or stop every five seconds or so and stir around the flour so the larger pieces get blended. Blend until you have the consistency you want. Make sure to store in an airtight container AFTER the flour has cooled off a bit.
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