Preheat oven to 350-degrees and line a baking sheet with parchment paper. Set aside.

In the bowl of a stand mixer, affixed with the paddle attachment, add the butter and brown sugar and mix until light and creamy. Add the vanilla extract and egg and mix on medium-high speed until combined.

Change the mixer to low speed and add the graham cracker crumbs, flour, cornstarch, baking soda and salt. Mix until just combined. Remove the bowl from the mixer and use a rubber scraper to ensure all the ingredients are combined. Use a standard-sized cookie scoop to drop cookie dough balls on prepared cookie sheet.

Bake cookies in 350-degree oven for 10-11-minutes. Remove cookies from the oven. Let cookies set on the cookie sheet for 5-10 minutes before transferring to a wire rack to cool completely.