Makes 4 large bagels.
*I do not suggest you try making your own oat flour unless you can be certain that you can get a fine flour texture. You'd be able to do that in a high wattage blender, but likely not fine enough in a food processor.
**Start with 3 tbsp water and work into batter. Slowly add more as needed. I have put a range here since many people have said their batter was too sticky and that's because every flour is milled differently and may be more or less absorbent.
If your batter is too sticky to form into a ball, add 1 more tbsp at a time of tapioca flour and mix in with your hands.
See my "troubleshooting tips" below.