Cream together both sugars and the butter until light and fluffy.

In another bowl, whisk together the dry ingredients.

Mix in the eggs and vanilla.

Slowly add in the dry ingredients. I did this in stages, scraping the bowl each time.

Add the chocolate chips to the cookie dough.

Chill the dough for an hour. Oops.

Drop onto a parchment lined cookie sheet. I used my favorite tool for the job. My trusty ice cream scooper.

Bake them in a preheated 350 degree oven for 9 to 11 minutes. Let cool for 5 minutes before removing from the pan.

Bake as usual, but during the last two minutes of cooking time, add the marshmallows to the tops of the cookies. You will need to press them in a bit and let them bake for another 2 minutes or until they start to puff.