Brown the butter
Melt butter in a saucepan over medium heat. Continue cooking, swirling often, until golden brown and nutty. Pour into a heat-safe bowl and let cool until soft but not hot.
Mix sugars and butter
In a large bowl, beat the cooled browned butter, brown sugar, and granulated sugar until smooth and creamy.
Add vanilla and milk
Mix in vanilla extract and 3 tablespoons milk until fully combined.
Add dry ingredients
Add heat-treated flour and salt. Mix until a thick dough forms.
Adjust texture
Add remaining milk 1 tablespoon at a time until the dough is creamy and scoopable.
Fold in chocolate chips
Stir in mini chocolate chips until evenly distributed.
Chill (optional)
Chill 20–30 minutes for a firmer, classic cookie dough texture.