First, to heat-treat the flour, place the All-Purpose Flour (1 cup) in an oven-proof dish and heat at 150 degrees C (300 degrees F) for 5-10 minutes.
To make the cookie dough, chop up the Butter (8 tablespoon) and add to a large mixing bowl. Add the Brown Sugar (3/4 cup) and beat with a hand mixer until nice and smooth
Add Vanilla Extract (1 teaspoon), Salt (1/2 teaspoon), then mix with a wooden spoon. Add the heat-treated flour and mix together. Add the Milk (2 tablespoon) and mix.
Finally, add the Milk Chocolate Chips (1/2 cup) and Dark Chocolate Chips (1/2 cup) and carefully fold into the dough.