1.
Preheat oven to 350 degrees. Line a baking sheet with parchment paper or a Silpat liner.
2.
Using a mixer, beat butter, granulated sugar, light brown sugar, vanilla, and salt until fluffy (about 1 - 2 minutes).
3.
Add egg to the mixture and beat until incorporated (about 15 seconds) and turn mixer off.
4.
In a separate bowl, whisk together flour and baking soda.
5.
Turn the mixer back to the lowest setting and add the dry flour mixture to the wet butter mixture while the mixer is on low until incorporated.
6.
Turn mixture off and stir in chocolate chips by hand.
7.
Spread batter onto prepared baking sheet and shape it into a 8 - 9 inch circle, about ¾ of an inch in thickness.
8.
Bake for 20 - 25 minutes or until lightly browned.
9.
Remove from oven and cool completely.
10.
When the Giant Cookie Cake is completely cooled, remove it from the pan gently, using two thin spatulas. Place it on serving platter and decorate using tube icing.
11.
Cut into wedges to serve.