The chocolate chip cookie layer is my Favorite Chocolate Chip Cookie recipe that I halved and changed just a bit--a tad more butter and flour to give it more structure, and the brownie layer is a Betty Crocker Triple Chunk box mix for an 8x8 pan (18.9 oz box). I used a smaller box so the layer would be the right thickness once spread over the cookie layer in the 9x13 pan. If you don't want to use a box mix, you can use my Fudgy Brownie recipe, or any other brownie recipe you love (just make sure it's a recipe for an 8x8 pan).
Notes: They are much easier to cut once cooled completely, so hang on to your horses and wait to cut them (if you can)**To adjust for my high altitude I added 1 tablespoon all-purpose flour to the dry brownie mix.
Chocolate Chip Cookie Brownies printable recipe
for the cookie layer
1/2 cup butter, softened
1/3 cup sugar
1/3 cup packed brown sugar
1/2 teaspoon vanilla
3/4 teaspoon baking powder
1/4 teaspoon kosher salt
1 2/3 cups all-purpose flour
1 cup semi-sweet chocolate chips
for the brownie layer
1 18.9-oz box Betty Crocker Triple Chunk brownie mix
1 tablespoon all-purpose flour
1/4 cup canola oil
1/4 cup water
1. Heat your oven to 350. Line a 9x13-inch pan with foil so the foil comes up the two long sides. Spray the foil and pan with non-stick spray.
2. In a mixer bowl, cream together the butter and sugars. Add the egg and vanilla, mixing well after each. Add the baking powder, salt, and flour, and mix well. Add the chocolate chips and mix gently until combined.
3. Crumble the cookie dough into the prepared pan and press into an even layer. Bake 10-12 minutes. The dough should not be cooked through, just enough to hold up when you spoon the brownie batter on top.
4. While the cookie layer is baking, prepare the brownie layer: In a medium bowl, combine the brownie mix, flour, oil, water, and egg. Mix well.
5. Very gently, spoon the brownie batter on top of the partially cooked cookie layer and gently spread it into an even layer. Bake for 20-22 minutes or until the brownie is set but still soft (not jiggly). Cool completely before cutting. To cut, use the foil to lift the brownies out of the pan; use a very sharp knife to cut into bars or squares.