Preheat oven to 325 F.
Line baking sheet with parchment paper (I used a round pizza baking sheet, but you can use a rimmed rectangular baking sheet if you don't have a round one).
In a mixing bowl, combine butter and sugar.
Add vanilla and egg and stir.
Stir in flour, cornstarch, salt.
Stir in chocolate chips.
Add corn syrup and mix until well combined.
Spread batter on to lined cookie sheet and bake for 20 minutes. Cookie should be golden brown.
Cool and decorate!