Preheat the oven to 350°F (175°C)
Grease a round or square cake pan
Cream together butter, brown sugar, and granulated sugar
Add eggs and vanilla extract
Mix in flour, baking soda, and salt
Stir in chocolate chips or other mix-ins
Spread the dough evenly in the prepared pan
Bake until the edges are golden and the center is set
Let the cookie cake cool completely in the pan
Remove from the pan and place on a serving plate
Frost or decorate as desired
Slice and serve