To make oat flour, add the oats to a food processor and pulse until the oats are a fine powder. Measure out a 1/2 cup of the oat flour and set aside.
In a large bowl, whisk together the all-purpose flour, oat flour, baking powder, baking soda, and salt. If adding in extra seasonings or herbs, do so now. Pour in the non-dairy milk and stir until dough is formed. Form the dough into a ball and let it rest in a covered bowl for 5 minutes.
Once the dough has rested for 5 minutes, lightly flour your surface and cut the dough into 8 sections. Cover the cut dough with a kitchen towel and rest for an additional 3 minutes.
Working with one dough section at a time while keeping the others covered, roll into a thin circle. Dust with flour if the dough is sticky.
Transfer the dough disk to a skillet on medium heat (oil pan if desired) and cook the flatbread, flipping when hollow air bubbles form on the surface or the bottom browns. Place the finished flatbread in a towel to keep warm. Repeat with the remaining dough.