Preheat your oven to 350F. Line a rimmed baking sheet with parchment paper and spread the flour out in an even layer on the parchment.
Bake the flour for 5-6 minutes, or until it registers 165F with an instant read thermometer. Set the flour aside and allow it to cool completely before making the cookie dough.
Add the softened butter and granulated sugar to the bowl of a stand mixer fitted with the paddle attachment (or use a large bowl and a hand mixer). Beat on medium-high speed until light and fluffy– about 1 minute.
Next, add the vanilla and mix to combine.
With the mixer on low speed, slowly add the flour. Mix just until no large lumps of flour remain.
If the dough is too dry, add one tablespoon of milk and mix on low speed to combine. If the dough is still too dry, add the second tablespoon of milk.
Enjoy immediately and store any leftovers in an airtight container in the fridge for up to three days. Bring the cookie dough to room temperature before serving.