In a small saucepan over low medium heat (or in a microwave safe bowl), add in chocolate chips, butter (or coconut oil), milk and honey. Stir occasionally until melted and set aside.
While chocolate is melting, place parchment paper into 8x9 pan and make oat flour.
To make oat flour place oatmeal into a blender or food processor and blend until it creates a fine powder.
Add in baking soda, salt, and cocoa powder to oat flour and pulse a few times until well mixed.
Add in eggs and vanilla into the blender with oat flour and pulse a few times. Pour about half chocolate mixture in and pulse in the blender.
Add the rest of the chocolate and pulse until completely combined. Pour into parchment lined baking dish and bake for 40-50 minutes until toothpick just starts to come out clean. Don't over-bake.
Allow to cool completely and slice.
You could use a different size baking dish, but you will have to adjust baking times. A larger pan will yield thinner brownie and a shorter baking time. A smaller baking dish will yeild a thicker brownie and longer baking time.