Whisk the dry ingredients (oat flour, flour, sugar, baking powder and salt) together in a large bowl.
In a smaller bowl, whisk the butter, milk, cooked oatmeal, honey and eggs together until thoroughly combined.
Gently fold the wet ingredients into the dry ingredients.
Heat a 10-inch cast-iron pan or griddle over medium heat until water sizzles when splashed onto the pan. Lower to medium-low.
Rub the pan generously with butter.
Dollop ¼-cup mounds of batter onto the pan, 2 or 3 at a time.
Once bubbles have begun to form on the top side of the pancake, flip the pancake and cook until the bottom is dark golden-brown, about 5 minutes total.
Continue with the rest of the batter.
Serve the pancakes hot, straight from the skillet or keep them warm in a low oven.
