Preheat oven to 350 degrees.
For the crust add flour, oats, brown sugar, baking soda and salt to a food processor. Cut 2/3 cup cold butter into small pieces. Add to food processor. Pulse until mixture resembles coarse crumbs.
Reserve 1 1/4 cups oatmeal mixture. Spread remaining oatmeal mixture into greased 9" x 13" pan. Press gently. Bake 10 minutes.
For the brownies melt unsweetened chocolate and 1/3 cup butter in the microwave in 45 second intervals.
Add sugar, eggs, milk and vanilla to mixing bowl. Beat until well mixed. While mixing gradually pour chocolate/butter mixture into wet ingredients.
Add flour and baking powder to wet ingredients. Mix.
Pour brownie batter over oatmeal crust. Sprinkle with chocolate chips. Sprinkle remaining oatmeal crumbs over brownies. Press gently.
Bake 15-18 minutes.
Cool. Cut into bars.