Line 2 baking sheets with parchment paper and set aside.
Pour oats into high powered blender {such as a Blendtec} and blend into flour. Set aside.
In a large bowl, whip butter and sugars until light and fluffy. Stir in vanilla and egg.
Stir in all dry ingredients, including the homemade oat flour until just combined.
Stir in chocolate chips.
Spoon cookie dough into 1/4 cup measure, level off and scoop out onto prepared baking sheets. Flatten evenly to be about 2-3 inches across. Place in the freezer for 20-30 minutes.
Preheat oven to 300 degrees and bake cookies 15 minutes or until just barely browned. {they won't look cooked in the middle.} Remove from oven and cool 2 minutes before transferring to cooling rack. Enjoy at room temperature or warm with milk!