First Make The Chocolate Chip Cookie Dough: Add flour, salt and baking soda in a bowl and set aside.
In the bowl of your stand mixer, cream together butter and sugars. Beat in vanilla and egg. With your mixer on medium speed, add flour. Beat until flour is incorporated. Fold in chocolate chips. Set aside.
For the Brownie layer: Combine flour, baking soda and salt in a small bowl and set aside.
In a small saucepan over low heat; add butter, oil, water and sugar. Stirring frequently, bring to a very low simmer, then remove from heat. Stir in chocolate chips.
Transfer chocolate sauce to a large bowl and whisk in vanilla and eggs. Gradually add flour mixture and mix until fully combined.
Pour brownie mixture into a 9x13 lightly greased or parchment paper lined baking dish. Using a cookie scoop, evenly drop twelve cookie dough balls into the brownie layer. *You may have extra cookie dough, you can freeze and use later. I had about six left.
Bake 40-45 minutes until a toothpick runs through the brownie later and comes out mostly clean. Remove from oven, let cool, slice and serve!