In a large bowl, combine butter, brown sugar, granulated sugar, and salt. Whisk until combined.
1 cup unsalted butter, ¾ cup brown sugar, ½ cup granulated sugar, ½ teaspoon sea salt
Add vanilla and egg, and whisk until thickened, about 30 seconds.
1 teaspoon pure vanilla extract, 1 large egg
Sift flour, baking soda, and cinnamon right into the bowl. Fold until no more dry streaks remain. Add graham crumbs and fold until mostly incorporated - you still want there to be streaks for a marbled effect.
2 ⅛ cups all purpose flour, 1 teaspoon baking soda, ½ teaspoon cinnamon, ½ cup graham cracker crumbs
Scoop or shape the cookie dough into 12 large balls onto a parchment lined baking sheet. Use the back of the scoop or your fingers to press into the middle of each cookie, making space for the filling.
Chill the cookie dough in the fridge for at least 45 minutes (or up to 2 days) or in the freezer for 15 minutes if you’re in a rush.