In a large mixing bowl combine the flour, bread flour, dark brown sugar, sugar, powdered milk, salt, and baking soda.
Give the dry ingredients a good stir with a large spoon.
Next, soften your butter. I recommend using your microwave, I did only about 10 seconds. Your butter should still be solid but softened just a little so it can be easily mixed into your dough.
Add the butter in with the dry ingredients.
Add the egg, molasses, vanilla and mix with a hand mixer until well mixed. Dough may seem crumbly at first but mix until it becomes more cohesive.
Stir in the chocolate chips with a large spoon.
Use a large cookie scoop (about 2.5 to 3 tbsp) to form your cookies.
Chill the dough for 1 hour in your fridge.
Bake at 325 degrees for 14 to 16 minutes. Let them rest for 10 minutes on the baking sheet.
Video
Notes
The cookies may not seem done when you pull them out of the oven but they will continue to cook on the baking sheet afterwards.
Don't forget to chill your cookies and form them into tall balls instead of regular cookie dough balls. These cookies are a thinner cookie like the ones at subway and will get too flat without the chill time.